Please log in.
Before you can vote, you need to register. Please log in or create an account.
Science: Energy Conservation
Decentralize the Power Grid   (+18)  [vote for, against]
An Energy Tank in every home (or something like it).

I understand that we do not build power plants far from cities for one reason because of transmission loss. We run into blackouts and problems with grid capacity because there is little incentive to overbuild the electrical grid. I was wondering if we could start building a better infrastructure by requiring some method of electrical storage in every new home. Call it the Energy Tank.

I imagine a fuel-cell device that incorporated an on-demand hot water heater, and could generate electricity from hydrogen or hydrocarbons. Where you would normally use space in a new home for a water tank, you would have this fuel-cell device. The connection with the hot water heater is to reduce energy consumption (on-demand is more efficient) AND to reduce the amount of utility connections needed (reducing cost). Also it would require little or no more space than an existing water-heater.

If every home had a fuel cell for energy storage, we could ease the burden on the grid during peak energy needs (basically running off a battery). Then you open the possibility of cheaper local production of electricity. The Energy Tank would use that solar panel or wind generator you have been thinking of purchasing to easily break water into storable hydrogen for off-the-grid generation. If your neighbors have some demand, and you have supply, reverse metering would let you sell the grid some of your energy.

I wonder how much conservation we would see without the need to push electricity from plants to homes. Also we would be less at risk of catastrophe/terrorism. The grid becomes web-like with lessened centralized resources.

I wonder how many people would purchase solar/wind or other sustainable energy collection devices if we could just plug them in to an Energy Tank for storage/distribution. Basically a capacitor in every home. You would gain the ability to run for a while during power outages, AND I imagine that plant-produced energy would drop in cost, since the cost of distribution/storage would drop.

Looking forward to comments...
-- trekbody, Apr 13 2005

Gas engine micro-cogenerator system http://www.gastecte...ngine/gasengine.htm
"In 1998, Japan's Honda Motor Corporation started the development of a micro cogeneration system for residential use." [half, Apr 13 2005]

Hydrogen from water? Too easy! http://www.scienced...03/050325234941.htm
[daseva, Apr 13 2005]

Domestic CHP system http://www.niesmart.co.uk/dchp.htm
Domestic energy generator [moomintroll, Apr 13 2005]

Microgenerators and the National Grid http://66.102.9.104...+grid&hl=en&start=4
This might be useful - frankly, I got bored halfway through. [moomintroll, Apr 13 2005]

Microturbines http://www.microturbine.com/
Well, if you have the need for 30 kW of power. [Worldgineer, Apr 14 2005]

Gridwise http://www.gridwise.org/
Goal: move our industrial-age electrical grid into the information age. [reensure, Apr 14 2005]

Ice Farming http://www.washingt...rticles/0402-a3.htm
[FarmerJohn, Apr 18 2005]

Whispertech http://www.whispertech.co.nz/
Boiler/generator [scubadooper, Apr 18 2005]

Thermal Energy Storage (TES) http://www.cryogel....orage_operation.htm
One way to do it [Zimmy, Apr 19 2005]

Ice based chillers: PDF FILE http://www.pinnacle...NW_EHS_Complete.pdf
Search for "Bank One Ballpark" [half, Apr 19 2005]

High Speed Flywheel http://beaconpower.com
Gangable high speed flywheel electricity storage you bury under your lawn. [skids, Apr 25 2006]

I think it sounds like a cogenerator (though I can't honestly say that I've ever heard a cogenerator in operation).
-- half, Apr 13 2005


Could my stored energy be used by others, giving me rebate incentives at the same time? that is, people would invest in energy storage, get a tax deduction or something, ease distribution and dish out energy at peak times for less. Like electricity's version of the small business. Yummy bun.
-- daseva, Apr 13 2005


Romulox - I think it's something we should give tax breaks for - but if you are just talking about getting paid for the energy you would send out to the grid - YES, that is what I meant by reverse metering.
-- trekbody, Apr 13 2005


I can't find the blasted link atm, but Invensys created an energy storage facility which was in effect a giant battery plugged into the UK national grid. Got sold to a co. called Enersys in the US.
-- moomintroll, Apr 13 2005


The problem with the gas generator is of course the pollution. You are just burning the fuel (releasing carbons). Not that using the hydrogen in natural gas doesn't do the same thing, but my hope is that having the hydrogen storage potential would lead to more sustainable methods of energy collection.
-- trekbody, Apr 13 2005


Caught red handed of skimming the last paragraphs, Yes, of course. Sweet. But, I don't think energy companies will let you buy and sell so obviously. There'll probably have to be some tax system to give people incentive to distribute.
-- daseva, Apr 13 2005


Allowing such a storage battery to be charged from the grid during off peak hours would also reduce the load on the grid.

This "energy tank" concept is done in a slightly different manner here to air-condition some of our sports venues. A large tank of liquid is frozen when energy costs are low (overnight) then the venue is cooled during the day by using the "stored cold". The municipality also distributes chilled water (in pipes below ground) from this plant to nearby municipal buildings to reduce the cooling costs there.
-- half, Apr 13 2005


Thanks half - I had considered mentioning that you could use other methods of storage, but defaulted to fuel cell to make it less complicated a description, and offer the potential of generating on-site from natural gas. Basically the fuel cell is a good battery if we can get it to work. You could replace with a flywheel or other efficient storage, it just seems to me that you can get a bit of synergy tying in with the hot water production, using the space the water heater would use, using the hydrocarbons many do (weening us off the hydrocarbons possibly).

Moomintroll - I am not certain costs would drop, but it seems that one of the problems we have is getting the utils to pay for growth in infrastructure. If we start reducing the need for the grid, it should be balanced out by population growth and growing energy demand (they can stop growing the grid if we are growing it, and they would not have to keep capacity needed only for peak times). I agree this might be a wash. Still, we need to move away from mining energy, we have to collect it sustainably.
-- trekbody, Apr 13 2005


I got a bit lost thinking about eco-generation and wasn't really paying attention to the storage bit. Was babbling, sorry. I see what you mean about being able to remove some capacity because peaks would be smoothed out.

The truly terrifying bit is the speed with which energy consumption in developing countries is increasing...
-- moomintroll, Apr 13 2005


Three words: Cars in china.
-- daseva, Apr 13 2005


Interesting Unabubba, but I wonder about the efficiency. IF (big if) it was equally efficient to cool air and cool the water, you would then have to pay to keep the water (ice) cool until it was used. It might throw effeciency off. In theory, a fuel cell would not have to expend any energy to be a in a ready state. Definitely curbs the daytime demand though.
-- trekbody, Apr 14 2005


This is a catalyst idea - For years now, we've heard the same story "Yes, there are sustainable, alternative energy sources. No, you can use them, because of demand-spikes, and our centralised power-distribution model." This is more than just an idea, it's a necessary requirement for non-polluting energy generation. [++++] If it takes off, it will instigate/allow for a rapid and sudden private take-up of renewable energy generation.
-- zen_tom, Apr 14 2005


"...you would then have to pay to keep the water (ice) cool until it was used."
The idea is that, particularly in a shopping center, it is used every day. You don't keep it cool, other than insulating it.

It won't pump power back to the grid, but such a system is great for smoothing out demand on the grid. On average, the grid has the capability of supplying the energy we need. It's the peak demand that kills the system. It's a different approach to the same end goal to "ease the burden on the grid during peak energy needs".
-- half, Apr 14 2005


The freezing water idea is interesting. I just wonder about the efficiency. You are right you do not have to keep the ice cold, except by investing in insulation. But insulation is not perfect, so there is heat infiltration, reducing the efficiency until it is used. You are forced to freeze more water so that there is enough to last by the time you start using it. I like it, just am very curious about the efficiencies.
-- trekbody, Apr 14 2005


It's a fricking block of ice--it costs close to nothing. Definitely less than standard A/C units. And supermarkets probably already have the space to store it.
-- yabba do yabba dabba, Apr 14 2005


[yabba] I think you're underestimating the amount of ice you need. Air conditioning is sized in "tons" - the amount of cooling capacity melting a ton of ice in 24 hours can provide. Considering residential units are about 3-5 tons, and 20 pounds of ice costs about $1, that's about $400 a day (not to mention the hastle of delivery). [trek] and [UB] are talking about freezing water using cheaper energy at night, and melting it during the expensive daytime rates.

I believe the only problem with the main idea here is efficiency. Until small generators get much more efficient it makes much more sense to generate the energy at central (and efficient, and relatively cheap) plants and wire it to houses. Although you lose significant amount of energy in transmission, you lose more by using small inefficient generators. Microturbines are fairly efficient, so we may see this with larger office buildings and manufacturing plants in the near future.
-- Worldgineer, Apr 14 2005


I understand your concern about efficiency. It seems very likely that it would be less energy efficient to do the cooling that way.

However, the context of the discussion has to do with decentralizing the power grid to reduce peak demand. It's likely that a finely tuned, massive power plant can directly produce electricity more efficiently than it can be converted to DC, stored in batteries and inverted to AC for use during peak power demand.

Same thing, only different.

Overall cost effectiveness, rather than absolute efficiency is more likely the driver in development of the freeze-it-overnight ice-block A/C system.
-- half, Apr 14 2005


Absolutely agree. I was commenting on the local energy generation concept. The freezing ice part is quite different, as it's still using energy conversion at large plants, just delaying it's use. They can be built quite efficiently and the only reason they aren't used more often is 1st cost and space requirements.
-- Worldgineer, Apr 14 2005


Oh, sorry, [world]. I was addressing [trekbody]. I didn't even see your annotation there when I started mine.

I agree with your agreement.
-- half, Apr 14 2005


Great comments everyone. I think zen_tom seemed to get my point best that if each home had the storage potential already there, the market for sustainable energy collection would potentially grow quicker. With the ability to just "plug in" that wind generator or solar panel or the like, you would get more people taking a stab at collecting their own energy. I for one would invest in a solar panel or wind generator (more likely in Minnesota), if it had a minimum of logistics, and immediate benefit.
-- trekbody, Apr 14 2005


There is a fellow in Canada (can't find the link) who's home is set up with solar and wind generation. He's tied into the grid, and any excess power he generates goes back into the grid, and Hydro pays him at a reduced rate for his hydro. He actually makes money off generating hydro.
-- Giblet, Apr 17 2005


//There's a shopping centre near here that freezes a 30 ton block of ice each night. It then uses fans to melt it during the day, to aircondition the centre. Like [half] said.//

I've often thought that freezing stuff when it could be done cheaply would be a good means of saving energy. My earlier thought would have been to have a residential unit which would freeze the ice in the winter (taking advantage of the heat released thereby) and melt it in the summer. The amount of ice required for those purposes would be large, but in rural areas not totally impossible. The biggest difficulty I can see would be keeping the water from freezing on the cooling coils themselves. Any idea how the shopping mall handles that?
-- supercat, Apr 17 2005


[Giblet] thats's great for those who can manage it, but very few can have a dam in their back garden. The centre for alternative technology in Wales (UK) has a couple of cabins specifically set up just to use solar and wind power - I stayed there for a weekend once. Basically, it's just about enough to run the lights. When it was really windy, there was a fight to see who got to plug their mobile phone charger in.
-- moomintroll, Apr 18 2005


Yeah, the power company in my city/town brags about their token wind-generator. My apartment uses more electricity than it generates.

Much of this discussion has to do with efficiencies of scale, which is to say that some things only pay off if done on a large scale.
Usually only the large power customers get offered electricity cost that vary through the day. If your power supplier will offer you variable rates, some forms of storage become cost-efficient. But that still doesn't get us to decentralized power generation, good idea though that is.

As an aside, a lot of alternative energy sources are dependent on the petrol-powered "grid" for their manufacture, transport or fuel supply. For instance: every wood stove I have seen is fueled by wood harvested with a gasoline-powered chainsaw, and transported in a pickup truck, often over an asphalt road.
So, yes to microgenerators, but be sure they can keep running when they are needed.
-- baconbrain, Apr 18 2005


My wood sawing and splitting is potato-powered.
-- FarmerJohn, Apr 18 2005


I understand that from a macro point of view distributed storage is a good idea, but as an individual home owner generating electricity, I would rather feed it back into the grid immediately, and have my electric meter run backwards. It seems simpler to store the energy credit as information in my meter.
-- farble, Apr 18 2005


I agree with [farble] I like the idea of distributed power generation, but I'm not sure that power storage is neccesary, useful or an efficient use of resources (money)

See link to whispertech website for info on a combination boiler/generator using stirling engine technology, as far as I'm aware plugs straight into the grid and as long as you can persuade your power company your meter should run backwards.
-- scubadooper, Apr 18 2005


Apparently transmission losses account for up to 10% of electricity generated, so if we could persuade everyone to have a wind turbine on their roof, or a combination boiler/generator then it would have a significant effect on the overall power distribution set-up. A 1Kw turbine has about a 2m diameter no reason not to put one on the roof if you ask me.
-- scubadooper, Apr 18 2005


[Moomintroll]

I never said a dam. I said Solar and Wind.

Very few people would be unable to have solar and wind generators due to location.
-- Giblet, Apr 18 2005


//Very few people would be unable to have solar and wind generators due to location//

I'd have thought virtually everyone could have them, whether the solar panels would be efficient or not is a different matter. There's no reason that I can see to prevent almost everyone having a wind turbine on the top of their house.
-- scubadooper, Apr 19 2005


"The biggest difficulty I can see would be keeping the water from freezing on the cooling coils themselves."

What problem do you see that causing? In the freezing process it doesn't seem like it would be too far removed from the way the refrigeration plant in an ice skating rink works. A second set of coils in the tank could transfer warmed water in to the ice and carry chilled water away to the air handlers in the buildings.

The system I referenced serves 10+ buildings with 34 degree water chilled by 3 million pounds of ice that is frozen overnight when utility costs are lower.
-- half, Apr 19 2005


Having water freeze on the coolant pipes would be bad for two reasons: (1) ice is a poor conductor of heat; if the coolant pipes got covered with ice, they would be unable to freeze much more water; (2) having ice form on the coolant pipes could damage them depending upon the shape of the pipes and placement of the ice.

It would seem that what would be desired would be a means of super-cooling the water without it freezing on the pipes, so that it would freeze later once it was clear of them. If the pipes were on the bottom of the tank, super-cooled water should float to the surface. Don't know how to make it freeze when it gets there (and not before), though.
-- supercat, Apr 19 2005


Though this whole AC discussion is a light sidetrack, something that people are missing is that in addition to the lower night-time electricity rates, your chilling equipment is also exchanging heat with cooler night-time air, which is also a mild improvement in efficiency.
-- skids, Apr 25 2006


Love this idea...
-- Cesiii, Jul 04 2006


This year is a landmark year - global micro power generation has just outstripped nuclear power generation, and it's growing fast. As far as I can see, the facility to feed the grid as well as draw from it will have to be introduced. I understand that it is rather tricky from an engineering point of view, but it is possible and therefore is a matter of when, not if.
-- wagster, Jul 04 2006


I was going to re-annotate this idea since Popular Science just had an article on energy generation, and it mentions micro-generation. Glad the idea is still valid. I'm not so sure I would be happy though if my TV was turned off by the microwave next door : (. I'm sure it would prioritize energy use, but it still seems somewhat commune-like.
-- trekbody, Jul 05 2006



random, halfbakery