The 'Sand Battery' that heats your home, NOT the planet!
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- Опубліковано 20 сер 2022
- The global energy crisis is starting to really hurt, and the prospects for winter fuel prices are starting to look pretty bleak for millions of people in the Northern hemisphere. So how do we get ourselves off our hopeless dependence on fossil fuels? And if the alternative is intermittent renewables then how are we going to keep our homes constantly warm during the colder months? Perhaps our friends in Scandinavia can provide some answers…
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I am 77 and find it so fascinating to live in the middle of a creativity boom around one of humanity's oldest problems, heating and light. Let 1000s ideas flourish and some solutions will stick. In the meantime, thank you so much for sharing bite size information nuggets about the ongoing process.
That's so nice. ❤ I'm younger than you. (ha, ha, but not by much)
I live inland East of San Francisco where the climate is much hotter and drier. My 4 bedroom home has wooden open beam high ceilings over half of the house that look great, but have no insulation. This house roasted in the Summer and was terribly cold in the Winter. In 2019, I needed a new roof and opted for having the entire roof coated with sprayed-on rigid urethane foam. It is 2 inches thick and you can jump on it without damaging the foam. They sprayed acrylic on top and dusted it with crushed tan colored mineral. This roof cut my natural gas heating bill 45% and since there is no central AC here, ceiling fans do a decent job of making one feel cooler. It was 102F, 38.9C a few days ago and it only got to 78F or 25.5C in our living room before the outside air cooled down for the evening. The attic gable fan used to run 12-14 hours a day in the Summer. Now it might run once a week for 30 minutes just before sunset if it was a very hot week. The thermostat is set for 95F, 35C to operate the fan. I'm retired and on fixed income and appreciate the savings on our utility bill. Maybe I'm saving the planet, too.
It's getting to a point where the idea of government should be more about prioritizing and funding development that benefits society as a whole rather than prioritizing profit making legacy energy production. Yes energy, in of itself, benefits society but at the cost of our future generations environment.
@@yodab.at1746 I want to see the cox ucking liberals, politicians, and big mouth news anchors live on 10 kilowatt hours a day of electricity like I do. I am able to pay for unlimited electrical usage especially on the 100F 38C weeks. But I made it my mission to prove that it can be done without many hardships. Government officials do not give a rat's ass about conservation of anything. Most are in to gain money, influence, power, and control over us peasants.
@@kimmer6 Better insulation is always a good idea, no matter what climate a home is in. You're definitely doing your part.
I'm working on the Eden Project geothermal system, were integrating the heated water to supply heat to a new greenhouse. The Geothermal system will supply surrounding houses an business's eventually. It's a great system with local losses at a minimum.
How deep are your wells? Where is it located?
I understand that it's very expensive to drill wells, especially deep wells.
You can use a compost heap in a greenhouse while the compost is degrading it releases heat to keep the greenhouse warm ..
I have a 5600 square foot office building which I heat with 6 450’ closed loop geothermal wells. The 50 year old building had two natural gas accounts, which I was able to close with a smile on my face. The project was a bit expensive, but the technology can become cheap by scaling up. I believe geothermal could be Europe’s answer to their recent shortage of natural gas supplied by Russia.
@@DrDave327 there is no shortage all what's going on is planned .. they are stealing everyone's money then they will steal everyone's savings then property's through default .. then banks crash and close then these parasites bring in programmable digital currency.. a social credit slavery system like China all run by A.I and if you don't comply with any rules your moneys switched off and were screwed all on. .Gov website ..
If you Google bank of England bail ins then you know it's all true..
Only hope we all have is to not buy into digital I.d on phones or it's game over for humanity..
Unfortunately half the country have no critical thinking brain cells left..
@@DrDave327 in addition, your capital expense will be inflated away and you will be insulated😉 from the volatility of current and future inflation and energy market price shocks caused by politically unstable states and corrupt governments.
Double whammy! Nice.
I love this guy! He always manages to adress and soothe my, sometimes paralysing, despair with hope and rational solutions. Thank you!
Cheers Andreas.
What do you guys make of the countless scientists who say it's too late to reverse anthropogenic climate change and that doom is inevitable in the coming decades?
Yes Andreas I agree. The problem is we are nowhere near doing sufficient to mitigate fossil fuel burning. Physics only cares about GHGs in the atmosphere, oceans and land masses. So how do we address that? Currently we're conservatively at 508 CO2 e ppm (NOAA Nov 2021). That roughly equates to an already 2.25 deg C global average rise, currently working its way through the planetary system, meaning roughly 7 to 9 degrees C over land. Yes, Dave Borlace is good at what he does, but let's not forget that humanity, whilst not reverting the dark ages, has to drastically and urgently reduce its GHG emissions. Most don't want to do anything, such as take action, to effect the change in reduction. There's no Polar Night Energy Storage System on a largely lifeless planet, so don't get too comfortable. There are no scientific tech fixes in the necessary time frame available... Sit David King, Prof Kevin Anderson, and more generally the Potsdam Institute, and the Tyndall Centre. These solutions are all for subequent adaptation, after humanity has stopped emitting as near as possible to low low close to statistical zero and taken >Trillion Tonnes of the stuff out of the atmosphere and kept it out. Good luck and kind regards
@@chrishayes5755 it could always be worse, less doom is better than more doom if we continue on the same path.
Why the obsession with so-called "fossil fuels" given that men (human beings have been using fossil fuels for thousands of years, without having any reason to suppose that there is any reason - or any sensible reason, why they might not?
Some years ago we built and used a so called Russian wood stove that was common in Finland. By heating the interior bricks to over 1000 Degrees, it took more than 5 hours for that heat to soak to the surface which was very nice for a single burn in the evening to last through a cold night. While heat capacity of brick is less than water the high temperatures meant we could store more heat than an equivalent size water tank. Basic idea seems feasible.
The Romans did it as well... works ✔️✔️✔️
there are domestic versions of this type of slow thermal heat radiations system available, cant find model name right now, that are based on ceramic thermal storage
All across former Yugoslavia (and I guess it was something copied from Germany), so called "electrical thermoaccumulation furnaces" with optional addition of timers have been used in winter time by the residents to take advantage of lower electric power price during night time. During the day, forced ventilation of ambient air through the isolated inside (a labyrinth of fire clay bricks) of the furnace works as space heater without conversions of energy from electric to thermal happening at the time of use. A thermostat prevents rapid discharge of all of the accumulated heat. The high temperature heat is produced by resistive electric heater lodged in between the fire clay bricks inside. A layer of glass wool keeps the core of the furnace from cooling too soon and also makes surface of the apparatus only lukewarm to the touch. So, basically, the concept of this solution has been known, but this is on a much larger scale and of cost-optimized construction.
I took an old electric stove I had laying around and filled the oven with sand and screwed it shut. I put 120vdc of solar to the lower element direct. Kept my greenhouse warm enough all winter. January I added another string of panels to keep it up the wattage. You can do it real cheap if you have access to some used panels.
I heat my house using a Finnish style fireplace, of my own design, that heats a 50000 lbs of stone in an insulated room. These fireplaces have to be isolated because of difficulty controlling its heat. I draw the heat from it through my furnace. It also heats 300 feet of copper tubing that allows me a 1 hour shower or more. The most important consideration is insulating the house. My house has a R-value of over 45. The windows a triple glazed and filled with argon. I live in Canada and before I completed my fireplace, I used to pay 30 dollars a month to heat it in winter. In summer, it is on average, 10 - 15 degrees C cooler inside than outside. I found the more insulation , the better. We also have an air to air heat exchanger that replaces the air in every thirty minutes.
I saw a gentleman that used a large barrel of paraffin wax to use as a heat battery. He put this 5 gallon barrel of wax on his wood stove. When the wood stove died down in the middle of the night, the wax gave off loads of heat until it solidified.
Around 10 years ago, I had the opportunity to visit a project in Richmond, Virginia using similar principles. A home-owner, who may have had an engineering background, though I do not recall for sure, had excavated a pit in the backyard - 10 to 12 feet deep and wide and maybe 15 to 20 feet long. This he lined with some sort of membrane to keep out water, insulated with foam board and layered in PEX pipe and sand. The whole was topped off with more insulation board and soil, and more membrane to keep out water. On one end of the system the pipe went to solar panels - I am recalling 4 or 5 panels - and to the house on the other. The PEX was filled with a propylene glycol solution. Richmond has fairly hot summers and cool to cold winters, roughly an average high and low in July of 89ºF/32ºC and 69ºF/21ºC, and in January of 46º F/8º C and 25ºF/-4ºC. The weather is rarely cloudy for more than a few days at a time. Heating of some sort is usually needed November through March, occasionally longer, and the home-owner said that the system kept up quite well. The house was of conventional mid century frame construction, and as I recall, had no special features except for good insulation.
Great video, Dave, cheers! Here in Saarland, Germany, there's a lot of community heating systems round power stations. Such heat storage systems would plug right in, no problem
Cheers Martin :-)
Not really tho as they are horrible inefficient. They require high temperatures for storage so either burning, solar concentration or induction. Germany has a massive energy problem in the winter (fully renewable), so using induction instead of a heat pump solution does not sound that great to me.
Instead of sand, you could use existing heat storage technologies namely PCMs (Phase Change Material). The energy required to heat 1kg of water or ice by 1°C is 1kcal. However to go from 1kg of ice at 0°C to 1kg of liquid water requires ~80kcal. Meaning you can store a lot of energy by using the phase change. You can do similar at higher temperatures with other materials, paraffin (candle wax) being an example here. Thus you could have a big tank of wax at ~75°C that you melt to add energy and freeze to remove energy. You can't store as much energy per area as with sand, meaning you need a bigger tank, however your max temperature is now 75°C so you could use a heatpump and be 4 times as efficient from an energy perspective. Now to be fair, there are challenges, for example Wax tends to expand when melting and a tank would have to deal with that.
@@_aullik sand is environmentally friendly, a ground-source heatpump heated hotwater tank in sand is good, with reticulated radiators, sized for heat storage with electric three or four hours at ultra-night rate, ideally including heatpump compressor direct-coupled vertical-axis wind turbine for free heating every time the wind blows (subsurface ground evaporator or built-in coolroom/fridge)
@@garygraham8373 Sry but you lost me there somewhere. Could you please split that into a couple short sentences.
What i understood from your text:
You want to use a heatpump, so your max temp is ~80°C or you are super inefficient. So what is the point of the sand instead of just using water tanks? Sand adds nothing to it. The water alone is a decent storage medium, however it is not that easy to insulate when keeping it under working pressure.
As for the heatpump that is directly coupled with a wind turbine. Whats the point of that? Wind turbines convert rotation to electricity and motors back to rotation. The overall efficiency is 80% to 85% efficient. A gearbox in direct coupling will get you around 90% efficiency. So slightly better, however now you are dependent on wind directly above you. Your heatpump is also less efficient as it cannot adjust its motorspeed depending on its needs. So direct coupling doesn't give you efficiency but it makes you a whole lot more dependent on the whether.
@@_aullik PCMs are a curious topic. Is the price and availability of paraffins or sugar alcohols trivial from engineering point of view? For sure the economically viable sources for petroleum wax will be fossil fuels, not some warm and fuzzy soybean oil.
Latent heat of phase change is a self-evident and an uninteresting insight. How do you freeze the material in the container(s) and how reliably does the crystallization occur? Please please, present a juggernaut of a tank filled with paraffin wax and the estimated storage capacity in GWh and the cost in €/MWh to me. Not some miniature nuclear reactor arrangement in a bucket at the basement of a technical university.
Finland here.
I live in city of Lahti which has city-wide distributed heating network - as all cities in Finland). The city has 2 own power plants that runs with trash (have been so since 90's) and nowadays with wood. They produce electricity and heat. Combined power is 350MW.
The scale of things here (Lahti has about 100K inhabitants, not all live in the area of the network) is so big that these kind of storage systems might not be viable. All the heat produced is needed anyway and burning plant is easy to adjust for current need. But in industrial buildings that may have their own plants etc. they may be great!
Anyway, we should eventually get rid of burning things altogether. Biomass isn't sustainable either. Lack of biodiversity in Finland is already actual problem. There's very little natural forests here.
What I think would be the best source of "unlimited" heat here up north is geothermal in industrial scale. There has been a test facility drilled in Espoo few years back (down to 6km or so) but apparently they won't be making commercial plant out of it - at least not yet. But the idea of getting all the heat needed from the ground should be very much on the top of the list. On winter there simply isn't any other scalable heat source here that wouldn't burn things.
Another problem with these distributed heat systems are that they're natural monopolies (fortunately they're almost all owned by municipalities). That way in many cases the price of that heat can be pretty high! Making a new house with good insulation and HVAC with heat exchanger consume so little energy that heat pump(s) can be much cheaper overall!
There's lot of wind turbines installed lately but their fluctuation is a bit too big of an issue in terms of creating heat. The coldest days in winter are in many case are the most calm.
Your last sentence indicated exactly why storage such as this is needed: store heat when there is excessive wind generation, and use it on cold nights with no wind. We need many different technologies for different scenarios if we want to successfully transition ourselves off fossil fuel.
@@mintheman7 Yes, I agree at some level. But the best way to utilize them would be to use the electricity to pump heat from the ground. Not sure if high enough temperatures for these storages can be gained there. But everything not burning is on the right direction!
@@ArcticSeaCamel You are still not getting my point. This technology is for energy STORAGE. Renewables are not viable unless storage technology becomes cheaper and more mature because wind/solar are both intermittent. Ground source heat pump you mentioned is very efficient when electricity can be generated, but how do you operate them at night without wind?
In Finland we have district heating in every major city and it's absolutely awesome. Very cheap and efficient system. I love to see this sand heat storage tech coming out of Finland when Nokia, Angry Birds and Clash of Clans are so yesteryear's news. If only those pesky Swedes hadn't made world's first fossil free steel (SSAB)... The race is on for a sustainable future and as we can see here, innovation isn't dependent on the size of the nation!
Technically, it isn't fossil fuel free. Most nitrogen is made from burning coal. It is then transported using fossil fuels. Check out watch?v=BaGO8jIxVdA
@@GrahamCampbell-kr2gz technically gold is free too, as are all raw minerals and food. Extraction costs a bit, but the lions share is company profits.
How is the heat use metered? How are bills calculated?
@@dougaltolan3017 Volvo claiming "Fossil fuel free steel" is BS on a large scale. Not counting the power to run a meter is insignificant.
@@GrahamCampbell-kr2gz I misread your first post here, sure, the steel isn't fossil fuel free but it could be very nearly if all heating was done without fossil fuel.
The metering aspect isn't a cost issue, rather a technical one. I lived in a place that had district heating, and billing was its complete downfall. Usage was measured by evaporation of water in a vial on every radiator. That meant that meter readers needed to enter every room if every flat. That simply was not going to happen, not on that estate anyway. Then there are all the ways to cheat such meters.
New England appreciates this video, especially with our (second hand) weather.
Another interesting heat storage material is sodium sulphate, which undergoes a phase change at from solid to liquid at 32C and can thereby story lots of 'latent' heat. The phase change temp is also adjustable down to 20C by adding common salt. This temperature range seems perfect for heating/cooling applications.
Most worth mention is, that you can use types of sands that are not usable e.g. for concrete. Since sand for concrete is also a very enviromental unfriendly (just search for some videos here) for these storages you can use any types of sand, e.g. from deserts.
Yeah. I'm still shocked that we don't use more lime-based mortar and less concrete, since lime mortar actually ABSORBS CO2 over its lifetime, while concrete adds to the environmental CO2, but so it goes. Freaking corporations and their dedication to big-carbon.
saudi arabia has plenty of useless sand.
Excellently written and presented. Thank you. Edit comment- you might check use of units in slides… kWh power vs. kW capacity.
To viewers wishing for small scale or DIY thermal storage, look into groundwater coupled heat pumps, and good old fashioned passive solar heat storage such as black stones or water drums placed inside sunny windows.
I recall when Billingham new town in the North East of England was built in the late 50's/60's, they implemented a district heating system with ducts along side the roads carrying the heating pipes. The system is no longer used, but the building housing the boilers and backup diesel generators still exists. It may have been still in operation until around 2010. I think originally the idea was to use the waste heat from the massive ICI chemical works to feed the system but I am not sure that part ever happened. It heated homes, college, shopping centre/precint and the large leisure centre.
There used to be central heating plants all over major cities. I remember seeing steam vents in the middle of a city street where they would put a big steel pipe over the crack or manhole in order to raise the steam above the road so it wouldn't wash out driver visibility.
New York city may still have places like that down in the older parts of lower Manhattan. Baltimore used to. Washington D.C. did, too.
The simplicity is amazing.
Here in Michigan there are thousands of old silos on farms no longer in use, imagine filling one with sand and putting solar panels every few feet surrounding them from top to bottom. Have some heat generating resisters in the sand and you have a massive sand battery! I only wish I had one 🤔🤔 Spray foam the inside for insulation, sure seems like this would work.
This is going off on a bit of a tangent, but I'm reminded of a blog written by a guy living off grid in the USA. He heated his cabin with a wood stove, which he buried under a pile of rocks in his basement, basically leaving only the door and draft controls exposed. That pile of rocks worked wonders to smooth out the "spikes" in heat output from the wood stove; he could fire it up when it suited him, and the rock pile would continue to give off heat long after the fire burned down.
I happen to know of this very same scenario in New Hampshire with a woodstove and all its piping in a brick room filled with tons and tons of sand and well that might be good when you have temperatures in the 40s when it’s 10 below zero you can’t get enough heat out of it it just burns wood so this caused the gentleman and his family to haul the tons of sand up the stairs and out of the basement take the brick walls down and try something else
@@theusconstitution1776 maybe a little heat pump that draws from the sand and brick thermal battery to access boost heat for cold snaps ?
Hi Dave, great video, I watch them every week. I design district heating systems here in the (UK). The industry is going through large changes as we speak. You spoke some of high temperatures needed. While this is important for certain sources, particularly EFW or where power generation is included in the scheme, the major trend is leading towards reducing temperatures in the systems and using more heat engines that can be powered by renewables. Heating design practices and regulations are both being geared towards low temp solutions that can be driven by heat pumps. If you want more details and some exciting happenings for future, let me know.
Cheers Jason. That sounds like very encouraging news for the UK. Thanks for sharing this info.
Thanks for your comment. It raised 2 questions:
1. In the lower temp scenario you described, would each home/bldg have a heat pump or some other form of heat engine that would tap into the district heating system?
2. What problems would lower temps solve and would those problems still exist in a sand-based high temp system?
Hi Joe, you can do it two ways. You can have a central heat pump and run the district at about 60C to feed the connections, or you can run the district at close to ambient temperatures (10-20C) and have smaller heat pumps at each connection. The latter generally means a lot of equipment however, which means lots of maintenance and higher front end costs. The former is a bit less efficient, because you loose more heat durning transmission.
The lower temps allow the use of heat pumps which can be powered by renewables, and reduce the heat losses from the network. Heat pumps also worke at a much higher per efficiency than combustion plant. The higher temp systems require a high temperature source, which usually means combustion. Green hydrogen could be used for higher temp systems, but the market and distribution of it hasn’t developed enough to implement them at any large scale. You can always put a high temp thermal storage system on a lower temp system, and it may be worth while if you are dealing with fluctuations in the power supply or some similar condition. You would have to heat the sand store with a high temp source however.
Hi Jason,
Floor heating only needs water around 23°C for a comfy feeling. That's 'cold' water...
Faucet water hardly needs to be more than 40°C.
Mostly these temperatures can be easily achieved tapping at 100 mt underground, and there you go...
At least here in the Netherlands.
What is you perception about that?
@@benzonex 40°C tap water has the risk of becoming contaminated which legionellae bacteria. That doesn’t seem like a great idea. There might be solutions for this that I’m not aware off btw.
Greetings from Kankaanpää, Finland. It's nice that people like you provide some optimism in a world that gets worse by the day, it seems.
An extension of this idea I've wondered about is using the heat for purpose as well as storage, even if that loses some capacity. Just about anything can be decomposed into its constituent elements given sufficient heat in a vacuum. So heat up difficult-to-recycle materials and then separate out the elements via gravity, spinning, etc. Cool the elements by transferring the heat to the district heating system, and then extract the elements for reuse.
One thing I can't quite get my head around: heat pumps are 300% to 500% efficient since they are not _generating_ heat but merely _moving_ it. This only works for low (human-scale) temperatures, though. For thermal storage, be it water at 98°C or sand at 600°C, you must use direct heat, which cannot exceed 100% efficiency.
So, while district heating from thermal storage seems like it gains a lot of economies of scale, I can't see how you can beat even small-scale heat pumps. Unless heat pumps are completely off the table because the outdoor temperatures go below -20°C or so. Which, come to think of it, is probably common in Finland.
Heat pumps are more efficient. However this and other thermal storage solutions are making use of existing wasteful processes.
Just like the example used in the video, Data Centres produce a ridiculous amount of wasted heat energy, which normally cannot be used and is just expelled. This then makes data centres very energy inefficient, even if renewables are being used to power the data centres a lot of excess energy is going to waste.
By storing this excess energy in sand to be released into exisitant district heating systems this then makes data centres more efficient as well as provide the district heating company stored heat for use whenever they need.
District heating is already a thing in a lot of central europe & scandanavia with incetives to join the district heating which also makes it more economical for people. This along with your comment on -20°C tempuratures really pushes this kind of technology.
This big picture view of the energy system, finding where energy is being wasted and turning that into something more useful, is way more sustainable and better for the environment than just sticking heat pumps everywhere because they are really efficient.
Can't wait to see this scaled up!
This is really good coverage
I use solar powered mini-split heat pumps. Along with a solar powered hot water heater. I use far less carbon footprint than most.
How expensive will Water become in the very near future?
@@Diana1000Smiles mine is $45 a month up to 1,000 gallons. Every thousand gallons past that is $3.75. not too bad. My friends are the management at our local gid. So I have a good understanding of our costs and maintenance.
What's a" mini-split heat pump"?
I'm looking to decarbonise my home and looking for all options.
Awesome, I went ground source heat pump 20 years ago and 6 years ago I added a solar system I live in a zone 4 climate and my home is 100% electric and all of this cost $45 a month last year, so it can be done and now I will find that last $45.
@@offgridwanabe Phenomenal!
Love these “lower tech” solutions to energy storage. I’m not at all against tech, but why not use appropriate tech instead of always focusing on high tech?
Keep up the good work!
Simple solutions are the future. High-tech brings with it high complexity, cost, maintenance, risks, etc. In systems design, we try to keep things as simple as possible to achieve the goal.
probably because of human curiosity, it's intense and fun. people love to create. Oh and remember, what we call low tech now used to be the current hi-tech, things always move forward.
Thanks for yet another excellent video. Please do regular follow-ups on Thermal Storage Polar Night's progress, competitors and alternatives
Really great video, there are a few companies working towards these same goals. One of them is Climatengine a private company I have done some work for. The project I was on was pool heating with basically no carbon footprint, really interesting project water was heated and at same time so was the indoor environment through new PCM materials for holding the harvested heat.
I have nothing to say really, but I appreciate your content, and wish to help with the yt-algorithms.
I guess I'd best reply then to pump the algorithm a bit more
+1
Heat pumps provides four times more heat than joule heating. Also, not using some change of phase (I.e. some salt compounds), implies that temperature has to drop quite a lot to recover most of the thermal energy.
What would be fantastic would be some compound that changes phase at temperatures appropriate for heat pump (50-60C), so that allowed them to be used directly at residential houses
Yes, but they aren't very suitable for most thermal storage because they aren't efficient at reaching the high temperatures that are wanted.
Thank you.
Can’t the sand bank be coupled w concentrated solar? Like cycling hot liquid when the sun is out. More efficient then converting electricity to heat.
Would like to know the reasoning as well.
CSP is more efficient, but also more expensive. Turns out, all those mirrors on individual trackers add up to a lot of moving parts that require a lot of manufacturing and installation costs, plus a lot of maintenance costs once deployed.
Many CSP sites have been built, but so far the economics of it aren't looking too promising.
I'm from Denmark. In my hometown, Holstebro, we have district heating using multiple sources which makes our heating very cheap. A lot of other cities have relied on gas, and they pay a huge price now. I think the "sand battery" is a splendid idea. We could use it here to store some of the solar energy that we have plenty of.
Why has it not been implemented here in Denmark, yet? Sounds like a perfect solution.
Sector coupling. For example a metal cast factory has a lot of heat it can be used for heatin, factory waste heat can be used and for example using the waste heat directly to heat up the Sand.
Especially in summer ( AC System get rid of the heat and below it in the sand
@@CUBETechie Sector coupling, yeah, I feel this is the way new energy systems must be designed. It's like a new "eco"system must be created, consisting of various kinds of energy components. This is in contrast of traditional "one problem solutions" like burning stuff to create energy, or even nuclear.
For example, the metal liquid batteries.. I'd like to see them put in a place where their waste energy could be harnessed.
PS. Hans, combined heat and power production gives a really high efficiency, over 90 %.
I see a more local, sustainable community approach to living becoming more popular in the years to come.
Verge Permaculture in Alberta has done engineered greenhouses viable through minus 40 degrees winters by pumping heat into ground under the greenhouse in summer while cooling the greenhouse, and recapturing that heat in winter while recharging the ground using cold air.
There is a pilot project in Massachusetts that is converting natural gas distribution to district heating. Which seems like an elegant solution to me.
Nothing elegant about destroying the planets ability to support human life. We have to stop burning fossil fuels
That's very interesting! I wonder how much retrofitting systems like that would cost.
Here in Denmark cities with district heating will have a mandatory connection requirement meaning it quickly works out for all parties. Also we are burning waste and putting the excess heat back into the district heating.
Same in Sweden.
The brilliance is in the simplicity
Brilliant. I wondered why something like this was not on the market. Chicago has had a similar approach, just for cooling, since 1985.
How does that work Matt? Interested.
Dave, it cooled down to near normal, but we had been roasting like hazelnuts in dry, sunny, relentless heat for a month and a half here in Wisconsin. Thanks for thinking of us across the pond! I just talked to an Indian gal who is visiting here from London; she was complaining about the heat in London, and she's from Central India! Keep as cool as you can, and keep up with the great presentations. Cheers! 🍺
I live in the US West, and the Wildfire Season is getting longer every year. All that smoke is a detriment to the Humans' respiratory systems. That combined with the US Opioid Epidemic makes for a poor survival rate.
Cheers Chuck. All the best :-)
thumbed simply for "we had been roasting like hazelnuts". 😁
@@Diana1000Smiles Sounds pungently spiced with roasted pine scent! I wish you well and refreshed by air purifiers. 🌱
Here in southern canada, plenty of summer sun and sand. Every Tom, Dyck, Harry and Dave could utilize a scaled down parabolic heated super insulated shed full of super heated sand in preparation for the next winter. Good job as always, keeps our minds busy. -(1.5c a tall order.
These concepts can be utilized in private dwellings, avoiding the long-assumed but mistaken perspective that centralized solutions are more desirable. For our home we use a combination of thermal solar to heat a 500 hundred gallon tank of water which circulates in radiant tubing in our house floor. This radiant tubing is ensconced in three inches of sand below wood and tile flooring. Once the sand heats up, it tends to remain warm with minimal added heat from the solar-heated hot water tank. Thank you for doing this sort of video, with alternative ideas that really work.
Thank you
Great video as usual, I'm not aware of any district heating in my area (California) but that's probably due to the major population centers being built directly on active fault zones. Sand as an energy storage medium is highly under utilized though and I love hearing about it being developed and the Ambri battery seems like its ultimate evolution, hopefully they will get a follow-up video
I live in the San Diego area and much of our downtown was heated by district heating with steam plants. I don't think any of it is used any longer and new buildings certainly wouldn't be using it. I found an article from 1987 that stated there were 40 buildings using it but that more and more were going to stop because the power company, SDG&E, was raising the cost of it. I think there are plenty of colder climate cities that still rely on steam heat.
And a massive thank you to you, Dave, for providing me with thought provoking videos on a weekly basis !
Cheers Ted. Much appreciated.
Great video Dave.
Dziękujemy.
Thank you so much Janusz. I really appreciate your support :-)
Keep it simple as the saying goes ;) Never thought of sand as a heat storage system, I was wondering how I could store all my excess PV over the summer to use in the winter after my immersion has topped out each day - this gives me an idea :D
Can you use a ground source heat pump coil to store energy?
@@kitemanmusic in theory, yes you could heat up the ground or a water source BUT importantly, you then need to expend more energy to get it back again using the HP - I'm not sure the efficiencies would make that worthwhile or practical from a plumbing perspective 🤔
@@kitemanmusic yes if you deposit the heat into the sand.
Dave,
Thanks for raising this important issue.
When it comes to heat, the laws of thermodynamics start to play a role. One that cannot be ignored! The Finnish heat battery uses resistive heating - which means 1 kWh of electricity becomes the same amount of heat, ie. 1 kWh. Because space heating only needs low grade heat (my underfloor system is typically at 30C) a heat pump can run with a coefficient of performance between 3 and 4. Which means 1 kWh of electrical energy "moves" 3 - 4 kWh of heat to usefully heat your building. If anyone currently has "surplus" renewable electricity, in my opinion at least, they should be using it to power a heat pump. If we were all doing this, it would create sufficient electrical demand to avoid any surplus, given the heating requirements in the UK. I appreciate that this doesn't solve seasonal heating requirements, but thermal mass, good insulation and control of infiltration in our buildings would go a long way to making this work in the UK.
One of the worst things western societies are doing is converting high grade fuel into low grade heat, particularly when that fuel is adding carbon to the atmosphere.
The steel, paper, cement and other process industries will be the main source of the waste heat.
Yes I thought about this too, but the amazin bit was, that they can store heat for months. Granted only for 80h of discharge, but it still lets one dream if we can offset summer heat / solar surplus towards the winter
If we're talking efficiency, nothing beats a proper heat pump. But the economics are much different, because the cost is much higher.
Yeah, Dave!
Your at the top of your game Doc,keep up the good work,this is stuff for now and the future.
As they say Thanks Loads.
You said they didn't use heat pumps to increase the energy density. However I missed the part on how data center heat was transferred to the sand silo. How did they get from, say, 95° to 600°?
From what I understand the heating is achieved by electrically heating water into 700 degree hot steam and let that run through a massive coil, basically. Once introduced the sand keeps the temps until it is time to let the heat out again.
This is primarily a replacement to central heating boilers.
They do it the other way around. Temperature of the air from the data center is about 60 degrees, but they do not transfer it into the silo. Instead the heat from the silo is used to warm up the data center heat up to 75-100 degrees which is then sent into the community heating network.
One thing that can be easily done in the meantime, …have your existing system checked for leaks, especially in an attic, make sure your ductwork is clean, have your gas / oil provider perform a tune up. I’ve seen hundreds of high efficiency hvac appliances installed into old infrastructure. This issue needs to be addressed.
Good that you mentioned other media as being possible for storage use. Sand prices in the us are up significantly due to demand for use in fracking operations.
Where I live in Finland we have a district heating system and I love it. However, storing cold during winter and distributing it through the district heating/cooling system for AC during summer, as they do on an office site in Helsinki, is my favourite tech innovation.
The only video this week, I have been waiting for :) Cheers Dave
Hope you enjoyed it!
Many, maybe most, large cities in the United States have a "district" steam heat system in the downtown/financial/industrial district, and it's not remotely new, been going for maybe 150 years. Currently powered mostly by various fossil fuels, but can easily be powered by renewables.
This type of tech would fit right in, and the systems could be expanded.
A major advantage is that that power companies, and many city planners and managers, and facilities managers will already be familiar with the concept. You won't have the hard sell of a new unproven high tech solution.
Thats it, plug in, have just one more connection to the teat.
The idea is to completely disconnect from metered life so that no one has the power to CONTROL YOU.
Oh, i forgot, you already live in a shoe box apartment with no facilities for even your daily coffee that you must SPEND AND BE HAPPY.
Maybe you could own nothing and be happy and penetrate ze cabinets for the bugz.
@@Ralph_Baric_PhD_C2019 What ars you on about?
'Northern hemisphere winter will be here soon enough'... I'm not ready.
I am ready. I cannot survive on smoke from Wildfires, and, I have lots of warm socks. 😊
Excellent and thanks for your explanation and inventory and the funtion of warming
Thank you so much for posting these fascinating videos. I get very depressed at times by the general state of the world and it is hugely reassuring to know that there are people and organisations out there who are doing positive things towards a better future.
Can Mother Earth support more than 8 billion Humans, currently? Also, check to see how many new Humans are born everyday on this Planet?
This will get solved Mikaela - to live more joyfully through these turbulent times, it is very important to realize your true self - you can read the books written by many different ‘gurus’ - I would highly recommend Eckhart Tolle - also watch his videos!
@@Diana1000Smiles not to worry the exponentially rising rate of death by heat exhaustion is getting ready, three more summer tops, to eliminate a great deal from that number. Just count the population from the equator thru the edge of the tropical zones that stay below, not sure, thousand feet above sea level, that’s a lot of people who if they becomes refugees fleeing those areas will make living much more problematic for everyone else. It is something the IPCC does not talk about! Just MHO I think there’ll be a billion of those refugees in no more than three more summers. What worse they will be concentrated fleeing thru the India Pakistan region! Still subsidizing the fossil fuels industry, one would think spending that money securing two substantial arsenals of nuclear weapons would be a bit less insane, considering the chaos created around all groups of pissed off refugees! But what if I’m wrong a little money not pissed away but spent on more security. Or the consequences of if I’m right?
@@Diana1000Smiles You need to look at the birth rates around the world. Right now, most of the developed world is in population decline, and the developing world will be following in their footsteps. And yes, Mother Earth could support more than 8 billion humans, but some of those humans can't get along with each other and have wars that disrupt the food supply. Climate change is obviously making things worse as well. The population of the Earth will eventually decline, but this has to be carefully managed to avoid demographic collapse.
Thanks Mikaela. Much appreciated :-)
One thing extreme heat waves impact is the climate change denial postings on UA-cam comments sections.
Awesome!
Grew up with district heating in our small town, courtesy of the local power plant. Shut down after the 71/72 heating system. The bill for our apartment was $6.40 for the season. :)
The Netherlands has some district heating. My city is planning on rolling it out in the coming years to replace gas heating. I won't be using it and have converted to heat pumps instead. The problem with district heating here is the single supplier that makes it very expensive.
Are there some areas where geothermal heat potential is good enough to combine with the sand battery? This system will find of competition with heat pumps, but they each have advantages and are better suited in certain areas. Bigger the variety the better, mapping out which systems work where is needed.
Yes there are such areas: in the Netherlands.
You should be knowing that Gilles de Brouwer...
I was camping along the Copper River in Alaska years ago with a buddy. Per an old woodsman manual I read as a kid, we dug a pit for our camp fire and put big rocks in the bottom. After we put the fire out or the night we filled in the pit with dirt/sand and put the tent over it. Took half an hour to feel any heat but after a hour it got so hot we had to move the tent. Was still warm in the morning. This is a great idea as the sand can be warmed by windmill generated electricity late at night when it's not being used elsewhere. But, living on acreage, I can't help but wonder about building a small scale model and heating it in the summer with parabolic mirrors?
Since I saw this last year I started planning a sand battery for my small home. I use passive solar for about 12 hours per day of winter heat, 300 days per year. I tested it the last couple years and find it survivable, comfortable at night if I use a mylar blanket underneath my bedding. Not suitable for edible houseplants. 17 hours is a good amount of heat.
I have concrete blocks and a big pile of sand and gravel inherited from the previous owner, but our heat dome had me put off starting it. At 69 I didn't want to press myself in 8 hour daily heat advisories.
I am excited to try this!
Worst case scenario my partially underground tea house is more stable in temperature, especially for summer.
I was glad to watch this again, as fall approaches, and I hope to complete by winter. It is interesting to see what the Corporate Succubus Slavers are doing, but I like low tech microsolutions... no debt, a garden, deciduous shade, and so on. An unusual improvement has been making original tapestries like in old castles.They increase comfort in winter and summer both.
Still studying transportation. My 05 Tacoma gets ~33 mpg, not too bad, I drive less and it is hard to beat.
Thanks Dave. Love to hear about these real life examples. Great to see that we have so many energy generation and storage technologies in the pipeline. The more combinations we have available the closer and more efficient a fit we can achieve depending on geographical location and need.
😄 a comment from the Stone Age?
Cheers Jim. Much appreciated
@@Diana1000Smiles Not sure I'm getting your point.
We'll be getting geothermal in my town soon here in the Netherlands
I look forward to having a think every week, cheers for your work 🍻
Cheers Daniel. Much appreciated
I live in the north of Ireland. We have had no extreme weather this summer. Our summer was very wet this year .
Obvious proof that sudden onset irreversible climate change is a hoax how dare anyone not go kiss the ass of your nearest petroleum executive!
I have envy. 💚
Create a warm sitting area with thick curtains hung from the ceiling in part of the living room or a smaller room. It's best to reduce the volume you need to warm to a higher temperature, what parts of the house do you spend the most time in? Focus on keeping a healthy warm temperature in the place you will spend the most time, other areas of the house only need to be kept at 12-15c tops. Unless you have genuinely serious health issues that prevent you spending a minute or two intermittently in a cooler temperature with decent warm clothing, which statistically you almost certainly don't, you don't need to heat the whole building through. It's good to think about what areas of your home are most central and which walls are exposed ect also, even what heat electrical appliances are creating heat and perhaps doubling that use up if practical. Bedrooms are better kept a bit cooler with warmer blankets and duvets and many a mattress heater, air quality is important for sleep so its good have "some" outside air exchange.
10 minutes with an electric heating pad on low under the covers before you get in bed makes a huge difference to sleeping comfortable. Cost is pennies.
I know, I’ll just fill my house with sand! I mean, the infrastructure is already there!!! LOL. Great video, and amazing how many environmentally neutral solutions there are. Be well.
You could have your very own full sized sand castle then🤣
Thank you. Hi, somehow do not agree with the comment that using sand has little or no environmental impact.
I know that sand extraction for construction is environmentally damaging and unsustainable in the long term, but that industry needs a particular type of sand such as from rivers whereas the sand in this idea can be from anywhere, e.g. the Sahara desert, so it won't have that negative effect on the environment.
Thank you
There are many ways
I’d really be interested to hear more about strategic planning for the local/national energy storage infrastructures needed for a clean energy future. Maybe about the numbers of (relatively small storage) facilities that might be required to keep the lights on. Also about the potential carbon costs of setting up these types of infrastructure. It seems to me that the technical issues about which types of storage systems are best, etc. are now secondary: there is enough technical innovation already to move on to questions about how to build smart, decentralised storage infrastructure in different nations. Of course it’s a huge generational project and will unfortunately require wise national political will, which is always in short supply, at least in the UK. Still, the move from a national energy model based around a few, massive ‘power stations’ to a model that involves huge numbers of smartly integrated local power storage facilities, simply has to be talked about.
Well, there isn't one. All the large countries in Europe, UK included, Eastern Europe rely principally on gas and coal and no one is planning to change anything untill, perhaps, 2050..
There are Baltic's + Finland where there is something in the pipeline, Denmark + Holland doing little bit as well, that's it.
@@petrskapa793 Why is it not being considered or discussed, though? It seems strange to me.
@@Parssel It's hard to say. Is it disinterest of the electorate, corruption pushed by the fossil fuel lobby, Incompetence of the decision-makers? I don't know. But the result is our dependence on Gazprom, Quatar, US, Angola, Azerbaijan... As well as the terrible effects of climate change, of course.
I was literally just thinking about this. I wonder if pairing this with heat pumps might be a good idea. Pulling the heat from attics and passing them through the thermal storage before pumping it into the ground.
I was in my attic the other day and thought then that a heat pump could easily provide the hot water I need.
@@dwftube I had to fix my ac a few years ago in the middle of the summer and I went into my attic. Got in about 6 feet and I felt like I was going to die. Learned my lesson real quick to vent the attic first. So much potential up there.
@@justbecause4557 But only during the warmer months - though I still think in the winter it could be better than outside.
That's a ground source heat pump and they work great if you can do it, expense and the ability to dig being the biggest barriers.
Too much heat in the ground will dry it out. Gotta watch out for that.
Beautiful
I love the concept, using readily available material to store energy. Unlike lithium-ion batteries, there's no toxic waste, no recycling challenges, and no rare earth metals used. I'd be interested to see if you could use a sand battery for a single dwelling, storing a summer's worth of excess heat and using it in the winter to run a boiler for radiant floor heating. I've seen simple heat battery systems for greenhouses, but this is the first time I've thought, "Maybe this can work for homes too."
Would be interesting to find out if I could use this system on a small scale for my house. I have suspended floors and have a lot of space underneath, perhaps I could fill a container with sand and heat it up during the summer and tap into it during winter
It would need to be a very big pit and a very energy efficient home!
@@pumpkinhead456 Look at this! It does not need to be big! Type of soil/sand is very important. Consult with experts. I think the isolating effect of the basement could be a good thing for heat-exchange between battery and house-floor.
People do something very similar with greenhouses already.
ua-cam.com/video/uTQ3FL0IGhU/v-deo.html
You can make it work. I have done it. Sand is not as quick of a transfer as water. The problem with water will be the temperature difference from top to bottom. Plan for a pump to circulate the internal temperatures. You can accomplish this with sand. Again much slower. The advantage to sand is the obvious. It does not boil and it does not leak…Storage is key if you have high heat demand. It changes virtually any heat source from city driving to highway. I have seen people use milk trucks to store heat. They are well insulated. You could run a wood stove for a day then have showers for a week. Don’t be afraid to try it.
My point was, to heat it in summer and run it in winter, it either wouldn't last long or you'd need a lot of sand. I calculated that I would get 4 days of heating from a milk truck buried under my garden :) obviously it depends on your heat requirements, but heating a home can take a lot of energy!
Thanks Dave for another wonderful video as usual, many thanks to patreons for their large-hearted contributions, via whom others like me can have access to First Class content.
If this tech absolutely successful and economically sound, amount of waste heat available is tremendous.
Suitable containers mounted on trucks could carry "charged containers" from thermal power plants to a vicinity of 200 to 300 kilometres, charged to megawatt levels by sheer waste.
That could be game-changer in many ways.
To do that, it would probably be better to use something with a lot more energy density than sand. A eutectic salt mixture with a high heat of fusion might fill the bill. Megawatt amounts of heated sand would be extremely heavy.
@@incognitotorpedo42 Such heat batteries, if successfully charged and discharged with heat, could bring a revolution in industrial fuels.
Interesting - thanks
Sounds good. I mean it just sounds like a heat battery with good retention properties so great.
FYI, I worked in R&D in home building many years ago. We build several experimental homes with super insulation, in Ohio, USA. The wall & ceiling R-factor was R-70. We used foam, wool, fiberglass and hay bale on different test homes. We found once the inside temperature reached 70 degrees F. If we kept the doors shut, the homes stayed warm for week or months. Also used 2, 3 & 4 panes in the windows. We proved it worked but owner did not want to spend the cost on normal buildings.
Replenishing warm fresh air is the clue there, especially in small volume houses.
The prior owner of my house got some insane deal on blown in insulation. I literally have 3 ' of blowin in insulation in the attic and double insulted storm windows. My utility bills are about $800 per year lower than my friends in similar size houses (lower both in the summer $100,$150,$200,$125) and the winter (About $35 less for 3 months).
So it's saved me about $18,000 over the 24 years I've been in the house.
What I think about this is that we could've had our cake and ate it too, if only we'd taxed fossil fuels correctly, according to their environmental impact. Other than cost, why would anyone choose natural gas over systems like these? I literally cannot find any downsides to these heat storage systems. They can use renewable energy when it's cheap aka during oversupply, helping to stabilize the grid. Their footprint is totally manageable and you could easily bury them in densely built up areas. They're made from dirt cheap materials and off the shelf components. They're positively low tech, so why are these not everywhere already? Why are we doing pilot projects only now?!
I'm pro-solar but we need to get ahead of solar waste. Perhaps with a $15 deposit on solar panels to encourage their return to a central location. And yes- if fossil fuel was properly priced (including $2 trillion for the gulf wars), we would be more likely to be on other diverse methods.
My experience of district heating systems in Russia is that the weak part of the system is in the distribution pipes, and in particular, the valves.
I think there are or used to be many federal buildings in Washington D.C. that relied on a central heating plant where larger boilers heated water to steam and then they piped it underground to buildings several blocks away. In some East coast cities you can still see steam vents in roads. There used to be a broken steam pipe on 17th street between Pennsylvania ave and H st, near the white house that they installed a chimney pipe over to lift the steam cloud over the cars.
Better insulation shade lighter colors on home.
For citys make roads any other color then black white pink green or yellow so we don't heat the road or blind the drivers.
Roads should have more native tall shade trees lining them to reduce co2 speeders heat bad air metals in the air and increase clean air full of o2 they hold soil reduce water evaporation and if it fruits food to if its edible.
Big hiway or freeways with 4 or more lanes should have public transportation trains in the middle to reduce traffic and air pollution witch saves money.
Parking lots should have trees thirsty cement mybe solar too.
Parking garage so it goes up should have solar and vine plants climbing the Parking Garage to add energy and reduces heat and adds o2.
Citys need to stop going out and go up make new laws where citys can be 50% urban minimum not 70% like now that will save land for forests and wild life save money and reduce logging a little bit too.
I always thought roads are the best places to have solar panels on the sidewalks. If roads are black, they will absorb more heat and part of the heat will be stored in for several hours.
Yes but alas the politicians in the USofA having the benefit of the people never in their minds, gave insane amounts of free tree pollen to their constituents instead of free fruit by eliminating female trees from the possibility of being planted. All that pollen with nothing to do, again, made the few wealthier than thou!
I love it.
Great for apartment flats.
On seeing this structure I couldn't help thinking of the old gasometer I could see from my bedroom window growing up. - plus ça change and all that.
100 degree weather has been fairly common since forever in my (northern) state. Sustained average higer temperatures is probably how warming shows through here.
Basically, our "super hot" days happen in the same quantity, but the average summer temp seems to have gone up very slightly.
Xcel Energy operates a steam and cold water service in Denver. I've also seen large central steam heating systems on US military installations around the world, though I don't know if those are being phased out as they upgrade buildings. Side note: Ft. Carson, CO is installing a large flow battery on the base. Not sure what prompted it, but it will be interesting to see how it works for them!
I live in Denmark with a lot of community heating. We have also many with solar heating . Several hundreds. And some with energy storing in hot water. We call it "damlager" in danish. Take a look on fx. "Vojens Fjernvarme", "Gram Fjernvarme" and one of the newest "Dronninglund Fjernvarme". I can see the potential about the high temperatures in hot sand for steem driven turbines etc. Thank You for sharing. I apreciate
Excellent film.
I'm interested to know how the stored heat is tapped off. Is it reverse air flow through an insulated heat exchanger?
I'm.hoping to.make a home version to try pre heating my domestic water.
Thats really nice, cheap ,clean and straightforward technology!!!
I remember in the 70s seeing a documentary, and in India these people just threw there animals dung in a trough, then stuck half a barrel on top and used the gas to cook on, well every house could have one of those that has a garden, because a compost bin is the same.
1:11 Dave, just a comment on video format. I love when you transition out the video intro with a question right before your title animation. Might be personal preference, but having a question instead of a statement I feel engages my mind a lot more, and in general it just sounds better than a statement.
Anyways, back to the video. Cheers!
excellent
There are district heating and cooling schemes in Canada.
I’ve done design work and advised on 3 of them.
Great video. A large part of my current PhD project is incorporating the same principles used by Polar Night Energy in to larger scale borehole thermal energy storage systems. In simple terms, I am investigating how to make the grout (used around the boreholes) electrically and thermally conductive, so that it can be used directly as an in situ resistive heating element for the surrounding sand/sandstone. Closed loop pipework, much like that used within the Polar Night Energy silos, would allow the system to be charged and discharged simultaneously, increasing versatility, minimising heat losses, and surface infrastructure.
What sort of temperatures are you anticipating? The problem with resistance heating is that it is very expensive. A heat pump run in reverse would put at least three times as much heat energy as electrical energy needed to run it, albeit at quite low temperatures.
@@rogerphelps9939 absolutely. I'm a massive fan of heat pumps, but to run efficiently they require a low temperature differential. Resistance heating is extremely efficient if you can minimise heat losses (I.e. by discharging from the outside towards a central "hot core"). The temperature I heat to will be the result of laboratory self-heating tests when an electrical current is applied directly to the conductive (and biomineralized!) grouts - something that I am yet to test. And of course CFD solvers for heat flow.
Couldn't you add electrical cables beside the closed loop pipes? What's the advantage of using the grout to heat up the system ?
@@MrCerdal primarily a better contact surface with the formation and greater volume. The grouts/slurries are largely made up of silica sand sand held together by a conductive matrix.
@@philsalter I see. Thanks. does this mean that success depends on the uniformity of the grout from top to bottom (and therefore a pretty good drilling team)? And is this technique only usable in continuous rock so that no grout escapes into softer layers?