Let buildings heat and cool themselves

How to kill coal in 10 years

Posted by Jon Rynn (Guest Contributor) at 9:15 AM on 20 Feb 2008

We know that coal is the enemy of the human race, what with carbon emissions, deadly air pollution, and unsafe and destructive mining practices. The supply of coal is becoming more problematic as well: recently, a Wall Street Journal article described a "coal-price surge," and Richard Heinberg has warned that coal may peak much sooner than most people expect. So what's to like? Not much.

But since coal-fired plants provide almost half of our electricity, we can't get rid of coal unless we find either a way to replace it or a way to reduce the use of electricity. Recently, Gar Lipow has discussed how friggin' cheap it would be to replace coal, and Bill Becker has pointed to several studies that show how renewables could replace coal.

I will argue in this post that if buildings could produce all the space and water heating, air conditioning, and ventilation that they need, we wouldn't need any coal. Heating and cooling buildings and water now consume 30 percent of our electricity and 32 percent of our natural gas.

If, for instance, geothermal exchange units (also known as geothermal heat pumps) were installed under every building, and an appropriate amount of solar photovoltaics were installed on roofs in order to power those units, we wouldn't need to burn 60 percent of our coal because we would not need 30 percent of our electricity. And because we could redirect our natural gas from warming and cooling into electricity generation, we could get rid of the remaining coal, replacing it with natural gas.

In other words, the buildings would both destroy electrical demand and free up natural gas, until renewables come online and replaced natural gas in turn. If we did this within a 10-year timeframe, we could generate millions of green-collar jobs, create new industries, and help the rest of the world kill off the rest of coal.

All of the data that I use in this post is available online in a spreadsheet I created called "EnergyUse." It has tabs for electrical use, natural gas use, my calculations concerning coal, and some notes on the data, all of which comes from the Department of Energy's Energy Information Administration (EIA).

So let's get electricity literate, and take a look at how electricity (and natural gas) are used in this country, so that we can figure out how to kill coal:

Heating and cooling: The EIA divides energy reality into four main areas of use, residential, commercial (which seems to include government), industrial, and transportation. As you can see in more detail on my spreadsheet, residential air conditioning, space heating, and water heating use up about 14 percent of all electricity and about 18 percent of natural gas; for commercial buildings such as malls and schools, 13 percent of our electricity is needed for heating and cooling and about 11 percent of our natural gas. Industry only uses a few percent of each for heating and cooling the buildings.

Buildings can provide this heating and cooling if geothermal heat pumps are installed below them. Depending on the building, pipes can be installed from 10 feet or so to 400 feet below the surface, because the temperature at a certain depth stays very constant, even in very hot or very cold climates. The geothermal units can take advantage of this heat constancy to heat or cool the building, depending on the need. Geoexchange does use some electricity, so in order to make the building self-reliant for heating and cooling, some solar photovoltaics would have to be installed on the roof, with some storage also available.

There are other heating and cooling needs that take up quite a bit of electricity, and as far as I know, the possibilities of using geothermal heat pumps to replace electricity for these other uses has not been investigated. Refrigeration, for instance, is a huge consumer of electricity, taking up 6 percent of all electricity in homes, 3 percent in commercial buildings, and even 1 percent in industry. The problem, I assume, is that the refrigeration equipment would have to be converted from being powered by electricity to working with heat pumps, which would seem to make sense since refrigerators are also heat pumps.

Another couple of large users of electricity are household washing and drying, at over 2 percent, and process heating in industry, at almost 3 percent. Again, these would probably have to be redesigned to accommodate heat pumps, but it would seem to me to be more efficient to use heat pumps than to create the electricity that then is used to mimic heat pumps.

Electricity for heat pumps: if we didn't want to use solar photovoltaics to power geothermal units, wouldn't we need to add back coal? Not necessarily. First of all, retrofitting buildings to retain as much heat as practical would probably cut down on the size of the geothermal unit needed. Second, if we could cut the remaining uses of electricity and natural gas down, we could use the extra natural gas and noncoal electrical capacity to power the geothermal units. In any case, it's to our advantage to decrease electrical use as much as possible. So let's look at the other parts of the electrical and natural gas landscape:

Lighting: There seems to be a certain amount of confusion concerning lighting, and my estimates will be on the low end of what you may encounter, because I'm using EIA numbers. With that caveat, we can see that residential lighting accounts for 3 percent of total electrical use -- and commercial lighting almost 9 percent. So Wal-Mart might be offering compact fluorescent lightbulbs, but they're probably wasting all of the saved electricity by lighting the huge buildings that they sell the CFLs in.

I chalk up the obsession with CFLs to the fact that it is one of the few places that individuals can easily make a difference. In fact, except for appliances, it can be about the only way to decrease electrical use through individual action, particularly if you rent. Everything else requires some form of social action -- and commercial lighting is certainly a good example. Which leads us to:

Electronic/Electrical equipment: Excluding refrigerators, washers and dryers (which are really heat-related devices), kitchen appliances, home electronics, and that researcher's nightmare, "Other", account for almost 10 percent of American electrical use. Most of these items could be made more efficient, saving probably a few percent of electrical use.

In the commercial sector, office equipment uses up 6 percent of our electricity. The industrial equivalent, machinery, uses up a whopping 14 percent; no doubt much electricity is wasted in both sectors. Finally, we have:

Industrial heating and processing, which uses up 23 percent of the natural gas consumption, and 5 percent of electricity. Much of this energy is concentrated in just a few industries, in particular, chemicals, plastics, petroleum, primary metals, glass, and some food processing -- these industries use almost 20 percent of all electricity (and 80 percent of industry use). Petroleum and chemicals use nearly 15 percent of all of the natural gas; so if we stopped using petroleum, cut back on chemicals and plastics, and recycled our metals, glass, and paper, we could reap a huge reward in electricity and natural gas saved and ensure that coal was not needed.

And what about the cost? There are about one million installations of geothermal heat pumps, but there are still many unknowns concerning the cost of carpeting the entire country in them. From my reading, for instance in this San Francisco Chronicle article, a 2,000-square-foot home would require $20,000 for a geothermal installation. And how much electricity would that take? I found one government document (PDF) that found that a 25,000-square-foot building required about 33,000 kWh to operate for a year; if the typical household uses 2,500 square feet, then 3,300 kWh/year would be needed, or about 9 kWh per day. If "1 kilowatt [of solar photovoltaic] will produce about 1800 kilowatt-hours a year," then we would need about 2 kWs for a typical household, or about $10,000 worth of photovoltaics.

With 100 million households, times $10,000 for photovoltaics and $20,000 for geothermal, that runs to about $3 trillion dollars for the whole country; if we assume commercial buildings use about the same amount of electricity for geothermal, then we would have to double the national bill to $6 trillion. Over 10 years, this would take $600 billion, which as I explained in my previous post, is most of the disposable military budget. No problem!

But the situation should be much better than that, because geothermal units pay for themselves within at most 10 years, so we could nationalize the Berkeley policy of loaning homeowners the upfront cost of installing equipment, paying the government back with the savings. The entire program could incur only the governmental cost of interest lost.

But I think we could do much better than that, for a few reasons. First, not all households need so much space, and multifamily dwellings are much more efficient than single-family homes because there is only one roof for many households. There should also be economies of scale for larger buildings in terms of insulating them. Second, our commercial buildings are often much larger than they need to be, with all of the attendant heating, cooling, and lighting. Finally, the way we lay out our cities and towns will be very important, both for efficiency of residential buildings and perhaps even more so, for commercial buildings, which should be much more energy efficient in walkable communities -- which leads to ...

Transportation: How would plug-in hybrids, or better yet, all-electric vehicles impact a coal-less economy? There were about 3 trillion vehicle miles driven in 2005 (PDF); if we assume one third of a kWh per mile, then we would need 1,000 billion kWh, or an additional 25 percent added to our electrical output.

On the other hand, the NYC subway system uses 1.8 billion kWh per year for about 8 million people, but that doesn't include the bus system; in order to figure out a minimal amount of electricity for the country as a whole for transportation, we would need to multiply that 8 million people by 40, and double the resulting number to include the bus system, yielding about 160 billion kWh, as opposed to 1,000 billion for an all-electric automobile society. So the range for passenger transportation, at least, would be from 160 to 1,000 billion kWh (I'll go into details on petroleum use in the near future, never fear!).

Resilience: Natural gas is certainly not a renewable commodity, although there may be some possibilities for generating methane in a renewable manner, but using natural gas for most of our electricity needs would have to be temporary. We should work towards a renewable energy infrastructure with many different scales: continental-sized, using high-voltage DC transmission lines; city-sized, using local solar thermal and wind farms; neighborhood scale, using some forms of cogeneration and smaller sets of solar and wind systems; and finally the building itself. The resulting system might not maximize electrical and energy output; but it would surely make society much more resilient, and help it start to make peace with the planet.

For story: Let buildings heat and cool themselves
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Tight Case for Solar

Check out this Fora TV presentation the first segment makes a compelling case for going solar now. Demonstrates land use, other resources would be trivial compared to current uses:

The Environment and The Politics of '08
http://fora.tv/2008/01/30/Environment_and_Politics_of__08 ...

Possibly the best Alternative Energy blog I read: New Energy and Fuel

by jabailo at 10:07 AM on 20 Feb 2008

Resilient Structures

I love the concept of not only "green construction" but now as you say "resilient structures." Please expand on the theme!

There are issues with cooling and heating degree-days but the concept is that as ambient temperatures depart from an average reference point of 65 degrees F, more energy is used.

Nice metric but the AMOUNT of energy indicated by degree-days is not linear ... the idea of geothermal and other passive systems is to maximize latent heat inputs and force the curve in a different direction (lower energy consumption).

Thanks for the Berkeley link but uhhh, isn't that a very moderate climate that does not require much heating or cooling, anyway? Minnesota and Arizona seem like more extreme examples where resilient homes and buildings would be a better investment.

Onward through the fog

by Sam Wells at 10:22 AM on 20 Feb 2008

Back to The Future

Oh how soon the automtive industry went back to producing fuel guzzling behemoths after the 73 oil crises. The few feeble attempts they made at producing a fuel efficient auto they could turn a profit on fell by the wayside like the dead Vega's found all over the road back then.

We all through away out Mother Earth News with the underground homes that maintained a 55 deg temp. Face it South East here in our part of the country and soak up the winter sun through a double insulated glass facing side. The big concrete heat sink floors would soak up the heat during the day and give it off at night when you pulled the big heavy curtains on the windows. You could get one up to a comforable room temperature with a candle.

Solar with battery storage, get off the grid and seperate solar hot water.

Those were the days!

Imagine what modern computer control systems would do for our old 80's underground attempts.

The eons of time and nature was good to us down here. It was not until we become civilized that destroying our habitat become fathomable or fashionable.

by Pompey Road at 10:30 AM on 20 Feb 2008

Energy savings

I converted my house to CFLs in the mid 1990.s not because of the electrical saving for lighting, but because the old light bulbs put out so damn much heat. What was killing me then as far as my electrical bill was concerned was the air conditioning. Why, I thought, was I wasting electricity twice, once to light my house, and once to cool the heat the lighting produced.

PC's are real electricity hogs. Apple builds a really nifty little computer, the Mac Mini. It has as much power as the big jobs, and only uses 25 watts of power. Most PCs waste 2 or 3 times as much electricity out of sheer inefficiency as it takes to run a Mac Mini. The Mini uses laptop technology, lower electrical requirements in the computing process.

Charles Barton

by Charles Barton at 10:39 AM on 20 Feb 2008

Excellent. Killing coal with gas displacement.

District heating with seasonal heat storage, solar concentrator industrial process heat, air-to-air heat exchangers, window shutters, clotheslines, attached greenhouses, Trombe walls, ground coupling with concrete slabs, hot water solar collectors, firewood, thermal mass, white roofs, shade trees, preheat all domestic water (reduces the additional mix of hot water), refrigerators coupled to outdoor winter cold, power management, CFL, recycled materials, insulation, air leaks, efficient windows, efficient appliances, and #1 - low-cost capital.

by sunflower at 10:47 AM on 20 Feb 2008

Nice link, Bailo....

...and the first speaker, Richard Perez, has a nice website with his graphic showing solar potential vs. everything else.

Sammie, I didn't think up the term "resilient homes", you did! Sounds good to me. I think that the exact systems people use would vary greatly from region to region, and even design to design, such as sinking part of a building into the ground, etc. Maybe in some places PV would work better, solar thermal in others, and storage options would probably vary a lot as well, but I think it should be a working hypothesis that in any region buildings could provide their own heat and cooling.

by Jon Rynn at 10:48 AM on 20 Feb 2008

Fine job Jon

Yes! Conservation with geo heat exchange. Powered by rooftop solar. Would replace coal completely over 10 years.

I think it's the best path for now. Let the other more complex and costly parts of a 100% renewable system catch up. Like plugin hybrids.

One note, Chicago hosts the nation's largest wind farm? With eggbeater style wind machines on buildings. is this rumor true?

That's why direct subsidies of 10 cents per kwh for renewable power from roof top solar, and 5 cents per kwh (or equivalent gas) for each kwh saved is the quickest simplest political path as well. It's payed for already, just take the money out of subsidies that energy companies no longer deserve.

http://amazngdrx.blogharbor.com/blog

by amazingdrx at 11:00 AM on 20 Feb 2008

Pump it up!

I think this post is spot on. There will be no silver bullet for our upcoming energy crisis and we will need all the tools we can muster. Stuart Staniford at the Oil Drum argues that global energy will plateau between around 2015-2025. He argues that renewables will take several decades to make a serious dent in our energy use:

With serious policy help, PV installed capacity can grow much faster than the 35% global average. Eg in Germany, PV has grown at a CAGR of 61% over the same 1990-2005 period. However, the global installed base of PV is miniscule - in 2005 it only comprised 0.0033% of marketed primary energy (on a thermal equivalent basis). The effect of all these trends - tiny current installed base, rapid growth, very fast learning curve, high EROEI tends to mean that PV can be of almost no meaningful benefit to the global situation in the short term, but in a couple of decades from now reaches critical mass, and then will potentially be in a position to provide almost all of society's power within a couple more decades from that.

So the sooner we get public policy that reduces our dependence on coal-powered electricity (and provides the upfront cost for building renovation), the easier it will be to reduce the chance of black-outs in the decades ahead.

Incidentally, the Oil Drum also has a recent post on ground source heat pumps. Apparently 97% of new buildings in Sweden are built with them.

by Colin Wright at 11:05 AM on 20 Feb 2008

BTW Grist writers

How is ocean current generation coming along in your area? Has anyone thought of the chicago wind farm model in your area? That coastal wind has to be pretty intense. Gusting over the city and burbs.

http://amazngdrx.blogharbor.com/blog

by amazingdrx at 11:12 AM on 20 Feb 2008

Can't find Chicago reference, drx...

...and thanks for mentioning that oil drum article Colin, some more good info there, if it works in Sweden, it must work everywhere...Also on Oildrum, diatribe from Robert Rapier on the difficulty of getting support for a carbon tax or higher prices...so why not just build it all, with subsidies/grants/loans? As Sunflower says, we need low-cost capital, which is the interesting part of the Berkeley experiment alluded to in my post.

by Jon Rynn at 11:23 AM on 20 Feb 2008

Political Gas

If we could harness all the hot air from the politicians we could heat the North East and provide enough wind generated electricity to light the West Coast.

The eons of time and nature was good to us down here. It was not until we become civilized that destroying our habitat become fathomable or fashionable.

by Pompey Road at 11:35 AM on 20 Feb 2008
[ Parent ]

Is this it?

http://netscape.com.com/Micro+wind+turbines+are+coming+to ...

Maybe largest potential wind farm? On all those tall buildings in the windy city. That's a lot of electricity to power heat pumps or heat exchange cooling with the earth.

I wonder if extra feedback loops in city water systems could supply a geo heat exchange source? You would have heat exchange coils around the city water line. The water would recirculate back through miles of buried pipe to exchange heat with the ground. no digging up everyone's yard that way. Or drilling wells all around your home. That's where the cost is. 15k of the 20k conversion per home?

http://amazngdrx.blogharbor.com/blog

by amazingdrx at 11:58 AM on 20 Feb 2008

more up to date

http://news.medill.northwestern.edu/chicago/news.aspx?id= ...

Urban wind farming.

http://amazngdrx.blogharbor.com/blog

by amazingdrx at 12:03 PM on 20 Feb 2008

energy from managed water systems

Here's a company which has patented a process that provides winter heating, summer cooling, and year-round domestic hot water, all powered by the thermal properties of pre-existing "managed water systems" like gray-water, re-used water, and potable water systems connected to large facilities, offices, or factories.

http://www.encoreenergyinc.com/page.php?page=technologyov ...

They're planning to install systems like this at 14 wastewater treatment plants in Massachusetts, harvesting the relative heat or cool of the enormous volumes of water in existing pipes, and turning out energy savings of up to 70% at those plants.

Erik

The Orion Grassroots Network: 1,200+ grassroots groups working for conservation & more

by Erik Hoffner at 12:03 PM on 20 Feb 2008
[ Parent ]

Excellent Erik!

A city water system maybe is next? With those feedback loops? With all the drain water heat/cold captured too. It's possible. It sure would help prevent winter water line freezeups and stop wasting water by leaving taps open in cold weather.

http://amazngdrx.blogharbor.com/blog

by amazingdrx at 12:09 PM on 20 Feb 2008

Another new phrase, DrX, "micro-wind"...

...this company, AeroVironment, says that their micro-turbine costs $6,000 for 1 KW (at least, that's what the newcast/video on that web page says), which is cheaper than PV, currently, although the systems are currently for commercial buildings, which I assume are stronger than residential.

I had ignored wind on buildings, mostly because of something George Monbiot said sometime back about wind turbines ripping roofs off of buildings, but that article indicates that technologies have come a long way since then.

If you google "daley center " wind, you get a bunch of articles on plans to put wind turbines on the Daley Center in Chicago, although I can't find anything announcing that they actually went up.

by Jon Rynn at 12:20 PM on 20 Feb 2008

Warm sinks

I've often thought that city water supply could be used, prior to distribution, for cooling concentrator high-intensity pv, pre-heating potable water a few degrees, and thus reducing city-wide hot water loads.

by sunflower at 12:25 PM on 20 Feb 2008

Great Idea, Dr.X. and Erik...

...This is a good example of systems thinking, by linking the water infrastructure with the energy infrastructure, they both benefit (also called positive feedback, or even co-evolution). Reminds me of some of the stuff John Todd has talked about; I remember his designs for cleaning urban water with water hyacinths, then raising tilapia fish, who would eat the hyacinths....Erik, maybe a post on this at a later time? I think it's worthwhile.

by Jon Rynn at 12:26 PM on 20 Feb 2008

Co-evoltion

It goes back to the Bucky Fuller kind of thinking. I keep wondering what Wright would do with solar PV, for instance.

A new era of organic design is upon us. Buildings and energy and water systems interacting with nature symbiotically.

Remember the Roman aqueducts? They used the water flow for energy too, water wheels to power grain mills. Somehow renewable energy systems remind me of it.

http://amazngdrx.blogharbor.com/blog

by amazingdrx at 12:45 PM on 20 Feb 2008

There's also micro-hydro...

here's an interesting video...but I can't find anything (through google) on using microhydro within water infrastructure systems, or if they make sense on buildings, they seem to be mostly from streams.

by Jon Rynn at 12:55 PM on 20 Feb 2008

Technically, we know how to do it

But, we can't have it all. We can't live in 3000-4000 square foot houses, drive Hummers, SUVs and pickups and expect to get anywhere. Big is bad. Striving to improve the fuel mileage of these cars is as futile as striving to reduce the heating costs of McMansions. We don't need any of these things to be more comfortable. We only want them because our peers have them. Break the cycle.

In the end, it all comes down to biodiversity. Poison Darts--Protecting the biodiversity of our world

by biodiversivist at 1:47 PM on 20 Feb 2008

One more

The beauty of geo heat exchange heating/cooling powered by solar is that it incorporates storage. The solar energy can be stored as heat or cold right there in the building that has the system installed. When the sun shines. It bypasses all the complicted storage schemes.

It gets the renewable smart grid going building by building paying itself off at every installation. That way it makes sense to start out on individual projects that pay and consolidate it all into a grid that is self supporting, energy wise and financially.

Solar cogeneration, getting electricity and heat from the same installation also helps.

http://amazngdrx.blogharbor.com/blog

by amazingdrx at 7:27 PM on 20 Feb 2008

How can the building store energy?

by Jon Rynn at 7:39 PM on 20 Feb 2008

Recipe from Amory Lovins

We have lived in such a building for 12 years and take it for granted. It stores heat in the winter and coolness in the summer. Our home never changes temperature. The comfort is amazing.

Ingredients:

Passive solar gain
Thermal mass with exterior insulation
Air-to-air heat exchanger
Window shutters
Summer night ventilation
Built to last 500 years

by sunflower at 7:54 PM on 20 Feb 2008

After enduring the 2003 blackout in NYC...

...I can appreciate any building structures that are self-reliant, at least in terms of heating/cooling, and some way to move water up and down a building. As far as PV being too expensive, my response is, and coal has been quite a bargain, hasn't it? not!

by Jon Rynn at 8:18 PM on 20 Feb 2008

JR, love the thinking

what is needed to make it work?

what will the market do?

what can legislation do to give the market a nudge?

who are the lobbyists now pushing the legislation you would advocate?

what other groups can we bring in?

by ce1907 at 9:54 PM on 20 Feb 2008

As heat Jon

Or cold for cooling in hot weather or for a freezer/fridge. Heat is stored in concrete floors, for instance, insulated from the ground with heat tubing through them. Phase change heat storage salt that stores many times the heat as thermal mass can also be used. It's great for domestic hot water storage.

Cold can be stored in the building thermal mass too, or for freezers and fridges with salt solution.

This way solar, wind, and off peak power from the grid can be stored using smart grid technology, in one home, or many homes and buildings gridded all up together. Heating/cooling is the major power use in homes. Water system pressure can even be stored.

It's quite a fortunate coincidence that the most electric power intense needs are heating/cooling related. Makes for low tech solar and wind power storage of the biggest load. plugin hybrids are the other big load, they have built in storage as well.

I think the storage problem is exaggerated given these features of geo heat exchange conservation and the smart grid possibilities for timing power use.

http://amazngdrx.blogharbor.com/blog

by amazingdrx at 10:25 PM on 20 Feb 2008

resilience; Cooper Union

"Resilience" is a good word, Jon, and a concept that we can live with.

This new school building, Cooper Union's latest pride and joy, is about ready for occupancy, on 3rd Avenue between 6th and 7th:

http://www.cooper.edu/cubuilds/insidestory.html.

It does not quite heat and cool itself, but its architects claim it is remarkably efficient, thanks in part to an open-mesh steel skin. We shall see how it behaves, in a climate of seasonal extremes.

Also, the elevator only stops on the 4th and 7th floors, in an 8-storey building, requiring a bit of healthful climbing and descending of stairs.

It may not matter very much, but the building seems to be conceived as a "vertical piazza," whatever that means. Unfortunately, the statement of intention by the architects of the Morphosis firm is an abominable piece of writing -- but, alas, typical of much stuff in that genre by artists.

Chickens deserve our true friendship! So do fish! So do other sentient beings! Let us learn to be kind.

by caniscandida at 11:06 PM on 20 Feb 2008

Great article, Jon

Just shows how far our thinking should extend. Now if only what is technically possible were to become politically possible...

Just a few quick comments on tapping in to the public water supply as a ground source as suggested by some commenters. I think this idea is likely to prove a non-starter for the following reasons:

It's no free lunch (surprise!). Existing water systems would need to be radically redesigned to transition from a one-way to a closed-loop system. The least this would mean is duplicating each and every water main to form the return. Hard to imagine this would be an inexpensive retrofit. Might make sense in a totally new water system - but how often do we get to do that?
Inefficiency. Existing water systems mostly don't run deep enough to reach the deep-body temperature of the earth. In the North they generally run just below the frost line. Hold your hands under a cold running faucet in Minnesota in the winter and ask how much useful heat you can extract from that!
Loss of system resilience. Far from reducing system freeze problems, taking heat from the circulating water during cold weather would substantially increase the likelihood of major pipe freeze, resulting in the potentially catastrophic loss of two critical utilities at the same time. No thank you.

But yes, yes, yes for ground-loop geothermal, properly considered and implemented. The technology is well-established in principle but general implementation is yet in its infancy. I have no doubt that the current upfront costs quoted by Jon would in fact be substantially reduced if it were to become as widely adopted as he proposes.

The true meaning of life is to plant trees, under whose shade you do not expect to sit.

by spaceshaper at 5:33 AM on 21 Feb 2008

transient heat

Spaceshaper, that may be true during cold weather, but it's not a huge issue to me. For one, heat exchangers are phenomenally good at extracting heat from cool water these days. And when it IS too cold, in the case of a municipal wastewater treatment plant in the north, then why not just turn the system on only when it makes sense, like to harvest heat from the mains swollen with the hot water from all those morning showers? Or they could just not turn that system off completely in the 2 coldest months if it is a problem. It's no huge thing. It'd still make a lot of sense for the remaining 10 mos.

The systems that harvest heat or cool from existing mains require no special engineering or construction, at least if you believe what's at the link I noted above...

Erik

The Orion Grassroots Network: 1,200+ grassroots groups working for conservation & more

by Erik Hoffner at 6:55 AM on 21 Feb 2008
[ Parent ]

Storage and water...

...to follow up on my micro-hydro comment above, I think in a water system that doesn't have pumping in the main lines, like NYC's very extensive system, it would make sense to put micro-hydro generators in at least the clean water.

As for home storage, I think that there is a lot to explore here, as much of the focus has been on large-scale storage that utilities would manage (in so far as there has been discussion of storage, see Jason Makansi's posts on gristmill).

I'm thinking of, yes, maybe hydrogen fuel cells would actually work in a building storage situation, for instance, a company called Renewable Energy International set up the first solar/geothermal/fuel cell combo in New Jersey, and plans one for the Cayman Islands (the offshore corporations need renewable energy?).

The other interesting storage technology is sodium sulfur batteries, which are too large for smaller applications like cars but might work very well for storing enough electricity to handle geothermal or other electricity needs from PV or small wind generators.

I don't think PHEV's would work too well for this, as they don't have enough storage, and I don't understand what's supposed to happen when you want to drive the car! Maybe for load balancing, or whatever, but not for building storage.

by Jon Rynn at 7:45 AM on 21 Feb 2008

Mall of America

Has no furnaces, just big windows and human body heat. They even need ventilation to cool it down in winter! That's heat storage.

Ahh well, Jon you need to look at the whole grid supply and demand and timing loads to meet supply. By charging PHEV at the right time, peak demand is reduced. From say charging them all at once.

You can only get power back out of PHEV batteries into the grid if the time they are needed for driving is preprogrammed into the system, so that there is enough time to charge up. Faster charging batteries are an advantage for this, but is it even necessary? I doubt it.

Heat/cold storage (with geo heat exchange)is the high load busting, low cost storage solution for a renewable smart grid. That's the big advantage over batteries or compressed air or pumped hydro storage.

"Existing water systems mostly don't run deep enough to reach the deep-body temperature of the earth."

Geo heat exchange does not need deep well ground heat that comes from the magma core. It runs on the solar energy stored in the ground. That 55% water is plenty warm enough to pump heat out of very efficiently.

Is running loops back through a city water system more difficult than digging up everyone's yard who needs geo heat exchange? High rise buildings do not even have yards. You can drill to get the ground heat but that is very expensive.

Of course it would be worthwhile to drill down to say 90+ degree geo heat for heating cities if it is close enough to the surface. I think that is the case with some cities.

http://amazngdrx.blogharbor.com/blog

by amazingdrx at 9:31 AM on 21 Feb 2008

How to implement?

I suggest carbon caps to start with. If you start funding these installations all over the country first, you'll drive down the cost of energy rather than remove coal plants.

The major problem is that of cost. Solar is not cheap, and neither is drilling geothermal wells. But if profit from carbon credits are used to fund financing for this, I can see it happening.

by Matt G at 10:30 AM on 21 Feb 2008

I say pay

I say pay the homeowner who installs geo heat exchange heating or cooling 5 cents per kwh saved over the previous running average of the last few years. That way the moving average eventually meets the present use, with conservation.

5 cents per kwh would pay out the most the first year, then as average use comes down less and less, until it equalized at the new lower energy use. by then the savings plus the subsidy would pay off the system. Giving the homeowner very cheap heat after that.

Even better with solar pV to run the heat exchange system, with a 10 cent per kwh subsidy. Free heat in a few years.

http://amazngdrx.blogharbor.com/blog

by amazingdrx at 10:41 AM on 21 Feb 2008

Solar not cheap swift boating from the dark side

Sunlight is cheap. PV is not cheap.

A passive solar home with insulated thermal mass is cheap and effective -- does not need geothermal exchange nor electric heat pumps. Low-carbon district heating is also cheaper than geothermal heat pump retrofits.

by sunflower at 10:54 AM on 21 Feb 2008

Hubris

I believe the original poster is off base on this one. It sounds like a college paper written from too late at night, cherry picking assumptions and skimming too wide a subject area to do it justice.

That said, I believe that drX is right on with his phase change salt storage method. Having such material in an insulated reservoir near a building might be a much easier option than drilling 200-400 feet down at yes, the cost is near $15k. My friend has an urban geothermal system and he did pay $20k, never sure if he'll see an actual cash recovery let alone in the 5 years quoted above in this blog.

I thought of the phase-change storage media several years ago but was unable to identify one that was readily available, noncorrosive, nontoxic and had the desirable properties of changing phase, say, right near 65 degrees F. With such a medium you would store excess heat all summer, and use it in the winter. Let's identify one and bring it into commercial development soon!

Efficiency losses are the other achilles heel of this discussion. Every time you transfer, change or move energy you lose some. Our buildings are not that well insulated yet either, unfortunately although Amory Lovins has shown us how to do it from scratch.

I also don't believe there is sufficient geothermal energy in the top 400 feet to have a purely self-powered heat pump. That would make its own pump power to move the heat for the buillding as well as power its own electricity needs. Unless you are in Rejkyavik or Yellowstone Park. Rube Goldberg devices, anyone? Somehow we neet to tap a natural renewable source, probably the sun.

Urban micro-wind is definitely one part of the solution in my opinion. That term is not new, just maybe to this audience. The OY Windside vertical axis turbines are most interesting to me due to the beauty and ruggedness, and lack of avian impact hazards. But they are expensive, no? Economy of scale needed now.

The thing about harvesting all kinds of energy from the tap water supply and the sewer waste system only works if those systems can handle the use (I doubt it) and if the cooling or heating of those media don't impede the function. I can affirm that right now, the tap water is da#m cold already at my building here in Ohio in February, you can't expect more energy out of a system than you put into it.

Moving toward sustainability with hopefulness, one revolution at a time.

by 2wheeler at 2:00 PM on 21 Feb 2008

Thanks, 2wheeler,

(except for the insulting stuff), I had never heard of salt storage, and micro-wind sounds interesting -- in fact, there is a lot of stuff that sounds interesting (two stuffs in one comment!), but the US government is too busy handing out billions to profit-rich oil companies and nuclear companies to spend a few pennies investigating these alternatives.

Considering that coal is horribly expensive when all of the externalities are factored in, it seems to me that even drilling all the holes needed for geothermal is well worth it, if cheap capital can be offered up front. At this point, governments at all levels, apparently, are needed to provide that capital, and looked at from a society-wide basis, the return would be much greater than just the individual return -- again, because of the incredible external costs.

Remember, we're talking about alternative costs here, if it's not geothermal, what is it? coal? The other point, however, which BioD raised, is that we shouldn't be dismissing viable alternatives just because it will make it difficult to heat and cool a 3000 sq foot house. The way our buildings are put together (and insulated) are a big part of the equation -- including big box stores and inefficient office buildings, remember, commercial use of electricity is almost as large as residential.

by Jon Rynn at 2:33 PM on 21 Feb 2008

The best system

The home to be heated or cooled would have plastic heat tubing in the concrete, with the concrete insulated from the ground with rigid foam.

For heating a heat pump would pick up 55 degree heat from the ground, with a loop of plastic pipe buried underground. The ground pipe can be trenched in or drilled in.

The heat pump elevates the heat to 90 degrees to heat water that circulates in the home's cement foundation plastic pipe.

For cooling in summer, water cooled in the ground loop circulates directly in the foundation loop.

So when the sun shines on pV panels on the roof, either the circulating pump for cooling or heat pump for heating, depending upon the season,the heat/cold is stored in the building foundation.

This storage effect can be enhanced for days worth of storage with phase change salt or frozen salt solution. Cold can be stored in a freezer this way.

That's how geo heat exchange would actually store solar or wind power. Anytime the wind blows or sun shines, heat/cold can be stored. Drawing on already super efficient geo heat exchange.

It would replace coal.

http://amazngdrx.blogharbor.com/blog

by amazingdrx at 7:52 PM on 21 Feb 2008

Why PV and not solar heating panels

Pv panels convert between 10% and 20% of sunlight falling on them into electricity. For less money per square foot, solar panels convert between 50% on 90% of the sunlight falling on them into low temperature heat. At least in heating climates, why not use direct solar heat instead of PV?

by Gar Lipow at 8:13 PM on 21 Feb 2008

New buildings use passive techniques first

There is no reasons new buildings should not use passive techniques (a combination of efficiency and passive solar) to reduce total consumption (not just climate control) by 70% in commercial buildings and by 80%-90% in residential buildings.

by Gar Lipow at 8:17 PM on 21 Feb 2008

Or a window ?

Despite increasing popular support for solar photovoltaic panels in the United States, their costs far outweigh the benefits, according to a new analysis by Severin Borenstein, a professor at the University of California, Berkeley's Haas School of Business and director of the UC Energy Institute.

http://www.semiconductor.net/articleXml/LN748261664.html? ...

by sunflower at 8:29 PM on 21 Feb 2008

eclecticism is called for here...

...(not that I can pronounce that word), but as I tried (not too eloquently) tried to suggest in the post, heat should be used for heat sources, electricity should ideally be used for motors, that is, most equipment. So if goethermal works, if passive works, if they both work together (thanks drx for that explanation), if solar thermal works better, use what's best according to the ecoregion you're talking about. Geothermal has the advantage that it is at least mostly heat-based, but -- and fortunately I read something Gar wrote before I completed this post -- it does use some electricity, and so some electricity has to be used for geothermal.

And again, insulation, ventilation, window-placement, wall placement, is all important -- I believe the fellow responsible for Architecture 2030 blogs here as well. This will all be hard for utilities to swallow, I imagine, so politically this isn't an easy sell. But it is doable.

by Jon Rynn at 8:38 PM on 21 Feb 2008

Sunflower,

that report seems somewhat flawed because he's just using standard economic arguments, and he just studied installations that were already installed, apparently in one area, not where they could be installed.

The proper comparison is with all of the costs of coal, and within the a system-wide approach, which is what I hope we are groping for here -- particularly, by separating the energy needed for heating from the energy needed for machinery, we are more able to get a clear view of a way toward a sustainable energy system. So, in the case of PV, the question is, what is a better way to power household equipment? Maybe industrial equipment should be powered from solar thermal farms sited right next to the factory, maybe PV/small wind makes more sense for a residential/commercial building for equipment. So the discussion should focus more on what functions we are trying to fulfill, no?

by Jon Rynn at 8:50 PM on 21 Feb 2008

The NPV of PV

I liked that the paper suggested pv subsidies would be better spent on R&D.

It is not a choice between coal and pv, especially in California. Coal is not a viable choice.

I saw no mention of the potential cost increase of pv with a carbon cost of $150+ per ton. The study was limited to CA climate. Nonetheless, the NPV of PV does not pencil out unless the application is off grid.

by sunflower at 9:38 PM on 21 Feb 2008

Of course

Cogeneration of heat for hot water from the PV panels would be great. And whole home solar heating from the panels directly and passive solar.

Would this replace coal alone? Probably not because not all homes or regions are suitable for passive or active solar or PV.

In these cases geo heat exchange heating/cooling is the best option. And these homes or buildings can still store heat from solar and wind coming onto the grid from other home solar pV and wind farms.

I'm advocating it all be used together in a smart grid, where homes like Lovins' supply their own heat plus extra power back to the grid... to be stored by other homes by capturing geo heat exchange heat or cold.

http://amazngdrx.blogharbor.com/blog

by amazingdrx at 10:00 PM on 21 Feb 2008

Political saleability

I really think it will be easy. Just stick to the subsidy point. The simple solution, money to homeowners to help pay off their investment in solar and geo heat exchange conservation.

No middle men, no traders, no power company deciding how much to give the customer and how much to keep from the subsidy. Most power companies simply keep the subsidy from RPC and only offset for customers who generate solar or wind kwh for the grid.

They don't actually pay when a customer generates extra power. They essentially steal it, and take the 12 cents per kwh or whatever RPC amounts to for themselves.

In New Jersey they let customers sell creidts on the open market. It amounted to around 20 cents per kwh!

http://amazngdrx.blogharbor.com/blog

by amazingdrx at 10:13 PM on 21 Feb 2008

Geothermal managed water supply

Nice article Jon. I like this site because it is positive and solutions oriented. I'll try to set the record straight on geothermal heat exchangers from the managed water supply. These comments prompted me, sorry spacesaver, all three points you make are not accurate. Geothermal HVAC from the managed water supply is the most efficient form of geothermal exchange there is. It is also the least expensive. The climate has no bearing, nor the existing water infrastructure. The process is extraction of the thermal properties of the water and returning it to the line. You don't actually use the water itself. Pressurized grey water, reuse water is the same process. Their is no loss of system resilience. The only limitations on grey water geothermal is all the states don't recycle water yet. CA,HI,NY,WA,NV,TX,CO,AZ all have pressurized grey water lines installed. And there is plenty of heat in Minnesota's pipes to be extracted, these systems are installed in extreme climates already, some of them back in 1983 are still there, operating as expected.

Brian

by Brian Mello at 11:04 AM on 27 Feb 2008
[ Parent ]

Great Brian

It's great to get real world experience here with these technologies no one seems to hear about.

What about the possibility of using water supply systems as a heat pump source (buffered by a separate loop of course) for heating and just direct circulation of a heat transfer fluid for cooling and dehumidifying.

Mabye heat wells drilled into the ground that loops of pipe go down into could boost the heat transfer from the ground as more and more building started using the heat (or cold) from the water system?

http://amazngdrx.blogharbor.com/blog

by amazingdrx at 11:14 AM on 27 Feb 2008

Geothermal

Yes that is possible, If I understand you correctly, however the current way the water is cooled again is just through a cooling tower before it is returned to the line.
In the very near future I'll post an even more excitng addition to geothermal from the managed water supply, very interesting, and no doubt will be the choice, the obvious, the future of geothermal exchange on a large scale, supported by a huge infrastructure. A natural fit(support) for what we are already doing.
Regards

by Brian Mello at 3:35 PM on 05 Mar 2008
[ Parent ]

Tell more, do.

Pardon my skepticism but I'm always ready to be convinced. How do you extract usable heat from 40° water (at least that's how I remember the cold water faucet in a Minnesota winter) without risking freezing it in the pipe? And if there are working systems in place how about some links?

The true meaning of life is to plant trees, under whose shade you do not expect to sit.

by spaceshaper at 4:37 PM on 05 Mar 2008

Geothermal HVAC from the managed water supply

Here is a link, and reference to geothermal HVAC from the managed water supply.

www.encoreenergyinc.com when there, click on the DeMarco Energy Miser Geothermal Video.

Units, systems, installed in very harsh climates. Operating as expected, for many, many years.

Regards

Brian

by Brian Mello at 6:34 PM on 11 Mar 2008
[ Parent ]

Who Needs "Buildings"?

Why do we need "Buildings" anyway? I mean, all people do is get in their cars and drive to buildings so they can sit in front of a computer.

They could do this more easily at home.

The real issue is to put more money in the hands of the people so they can control their lives instead of having to be put on the milk machine from 8 to 6 every day.

Possibly the best Alternative Energy blog I read: New Energy and Fuel

by jabailo at 8:16 PM on 11 Mar 2008

Bailo, you have a point,

although you're talking about a subset of what are referred to in the statistics as "commercial" buildings. We still have to worry about residential and industrial buildings, as well as stores (ok, unless shopping is mostly on-line, mr.soa)

by Jon Rynn at 8:58 PM on 11 Mar 2008

ADVERTISING POLICY

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