The Frugal Genius of "Swarm Power"

[Zeno Swijtink]

The Frugal Genius of "Swarm Power" - Lisa Margonelli
The Atlantic


The Germans have found a new way to solve a classic greenhouse gas logic puzzle while keeping their auto assembly lines running.

The puzzle: What's the cheapest way to increase electricity generation while reducing carbon emissions, bearing in mind that installing more wind and solar will require investing $2 trillion in new transmission lines and a single 1 Gigawatt nuclear power plant now runs about $17 billion?

Two additional facts: Generating electricity accounts for 41 percent of US greenhouse gas emissions, and two-thirds of those emissions are the result of energy being lost as heat, i.e. wasted.

The German Answer: Put thousands of VW workers on the assembly line to make home-sized natural gas furnace/hot water heater/generators. These generators, based on a natural gas engine already used in the Golf, are 92 percent efficient (because they can use the waste heat for heating water or homes) and can either produce electricity for home use or put it out on the grid. In other words, they're removing much of the second fact (waste), and also removing the need to build many more transmission lines. And, if the company Lichtblick is to be believed, they'll be creating the generation capacity of 2 nuclear power plants (2 Gigawatts) by installing 100,000 of these units in German homes at a total cost of $1.5 billion. (Far cheaper than the nukes, with no radioactive waste or risk of its weaponization.)

But wait, this is more than a fancy furnace. It's also a business model and a stealth energy policy. The units, networked together as "SchwarmStrom" or swarm power could be turned on and off by a smart grid controller to balance the mix of wind, solar, nuclear and what all on the grid at a given time, earning homeowners some bonus money for the power they generate and eliminating the need for some of those transmission lines and backup generators to deal with the ebbs and flows of wind and solar.

And then there's the super ultra unasked bonus question. Two percent of the US's greenhouse gas emissions are from manure ponds alone, and more are from municipal sewage and landfill. The Swarm Power generators could run on biogas, reducing methane emissions from manure AND emissions from coal fired generation in one go.

VW isn't the only car company working in this space; Honda also has similar unit. I haven't heard that US companies are working on this idea, but it would be a good three-fer as a stimulus program: build the engines, do away with the $8000 tax credit for first time home buyers and just give them a combo furnace generator; and jump start the process of building a smart distributed grid with lower CO2 emissions. Having a power plant in the basement has a certain Little House on the Prairie appeal too.

But will we? I think this is the kind of pragmatic path US policy makers are likely to miss. They're so focused on BIG GREEN projects like offshore wind or floating windmills and on small chartreuse projects like corn-derived disposable silverware and CFL lightbulbs that the vast middle ground of wasted energy is ignored.

Look at this chart of energy flows--it's a giant bowl of spaghetti and meatballs with 99.2 quads of energy entering on the left and 42.15 going to work on the right. (Note the tiny vermicelli like threads contributed by wind and solar, and the enormous lasagna noodle of waste aka "rejected energy"--57 Quads!)

https://publicaffairs.llnl.gov/news/..._EFC_20081.png

If you can get beyond the geekiness of the image, there's something poignant about it. Weirdly, it reminds me of the Andrew Wyeth painting called Christina's World, where the paralyzed woman in the dress crawls slowly across a rolling field. The energy flow chart is a portrait of paralysis--of policies and prices that have made it more profitable to waste energy than to put it to work. Stare at the broad gray lines depicting waste and see frittered potential, a failure of can-do, a sad stasis of the imagination. Christina, of course, didn't make her world, but we've spent generations making the flow chart and we have to figure out how to un-make it. Swarm Power is a good place to start.

[Sciguy]

A few observations:

First, this is still a way of increasing the installed base of fossil fuels. Like filling the roads with gas guzzlers and the hills with coal plants, it is very difficult to turn it all around when the fossils reclaim their fuels later on and we wake up from our petroleum induced reveries.

Using the previously unused heat makes good sense. When I lived in
Copenhagen forty years ago, the central power plant not only produced electricity but it had hot water pipes going out to houses and apartment projects around the city. That heat wasn't wasted either. Breaking the power plant into house sized pieces has the same advantage.

What puzzles me greatly is the discussion of distribution networks. On the one hand, the distribution network for natural gas is taken as, well, natural, while the distribution network for electricity is seen as expensive and problematic. I would expect the reverse. Gas in pipes is tough to distribute. Pipes leak, they corrode, they are usually buried at significant cost. If the distribution system is tankers on highways, that may be easy for propane, a liquid, but gas requires airtight, leakproof, high pressure tanks. Now compare that to copper wires up in the air, with nothing inside of them except electrons, nobody driving over them, no gas leaks into the atmosphere. The whole idea of bringing natural gas to every home makes no sense to me except if you are already committed to a fossil fuel based network of vehicles and roads and some pipelines. But for the future, investing in a grid that will bring electricity from where the wind is blowing or the sun shining, to where the energy is needed, makes a lot more sense in the long run. Why do these writers always want to ridicule the small contribution of solar and wind as though those were defective, stumbling children, incapable of becoming adults, rather than the victims of greedy petroleum companies and their compliant politicians? Solar and wind are the future, natural gas is just a temporary, dumb idea. So I hope we can find a better solution to using waste heat than this one.

[pbrinton]

Hi Sciguy

While I agree with you completely on your main point, you should not be so quick to defend the centralized distribution of electricity as being in any way efficient. Apart from the significant costs of maintaining overhead wires, with their vulnerability to weather, trees and human carelessness, there are two big and little-known issues. One is line loss; you get less power out of the end of a line than you put in at the start, and the longer the line the greater the loss. More important is the problem of voltage conversion. Voltage is loosely analagous to water pressure in a hydraulic system, and voiltage conversion is done with transformers. These range fromn the things you plug into the wall to power your cell phone charger, up to the gigantic arrays you see at electrical power plants and substations. The little-known fact is that each transformer wastes at the very best around 20% of the power. In reality the waste is much greater, as transformers are most efficient at peak load, and considerably less efficient at low loads. No system runs at peak power for any significant percentage of the time, so the actual loss if probably more like 40%.

Most electricity is generated at relatively low voltages, and used (in electronic devices) at even lower voltages, but to send it over long wires requires a much higher voltage. Therefore between generation and end use, there may well be five or six transformers, each wasting 20 to 40% of the power going through them. To save you the math, four conversions at 70% efficiency leaves you with a fraction over 24% of your original power. So to put it another way, you have to generate four times as much power as you need. And in the real world the numbers are much worse than that.

Small scale local generation, preferably from renewable sources, is the only way to reduce these inefficiencies.

Patrick Brinton

A few observations:

First, this is still a way of increasing the installed base of fossil fuels. Like filling the roads with gas guzzlers and the hills with coal plants, it is very difficult to turn it all around when the fossils reclaim their fuels later on and we wake up from our petroleum induced reveries.

Using the previously unused heat makes good sense. When I lived in
Copenhagen forty years ago, the central power plant not only produced electricity but it had hot water pipes going out to houses and apartment projects around the city. That heat wasn't wasted either. Breaking the power plant into house sized pieces has the same advantage.

What puzzles me greatly is the discussion of distribution networks. On the one hand, the distribution network for natural gas is taken as, well, natural, while the distribution network for electricity is seen as expensive and problematic. I would expect the reverse. Gas in pipes is tough to distribute. Pipes leak, they corrode, they are usually buried at significant cost. If the distribution system is tankers on highways, that may be easy for propane, a liquid, but gas requires airtight, leakproof, high pressure tanks. Now compare that to copper wires up in the air, with nothing inside of them except electrons, nobody driving over them, no gas leaks into the atmosphere. The whole idea of bringing natural gas to every home makes no sense to me except if you are already committed to a fossil fuel based network of vehicles and roads and some pipelines. But for the future, investing in a grid that will bring electricity from where the wind is blowing or the sun shining, to where the energy is needed, makes a lot more sense in the long run. Why do these writers always want to ridicule the small contribution of solar and wind as though those were defective, stumbling children, incapable of becoming adults, rather than the victims of greedy petroleum companies and their compliant politicians? Solar and wind are the future, natural gas is just a temporary, dumb idea. So I hope we can find a better solution to using waste heat than this one.

[Dram]

So if you want to prospect for gold you can and there is a procedure, but if you want to prospect for electricity at the Oceans edge only counties or PG&E are recognized players. It would be curious if individuals could have access to Ocean waves to make electricity and use it right there to make things instead of huge distribution networks. Can it be done?

Hi Sciguy

While I agree with you completely on your main point, you should not be so quick to defend the centralized distribution of electricity as being in any way efficient. Apart from the significant costs of maintaining overhead wires, with their vulnerability to weather, trees and human carelessness, there are two big and little-known issues. One is line loss; you get less power out of the end of a line than you put in at the start, and the longer the line the greater the loss. More important is the problem of voltage conversion. Voltage is loosely analagous to water pressure in a hydraulic system, and voiltage conversion is done with transformers. These range fromn the things you plug into the wall to power your cell phone charger, up to the gigantic arrays you see at electrical power plants and substations. The little-known fact is that each transformer wastes at the very best around 20% of the power. In reality the waste is much greater, as transformers are most efficient at peak load, and considerably less efficient at low loads. No system runs at peak power for any significant percentage of the time, so the actual loss if probably more like 40%.

Most electricity is generated at relatively low voltages, and used (in electronic devices) at even lower voltages, but to send it over long wires requires a much higher voltage. Therefore between generation and end use, there may well be five or six transformers, each wasting 20 to 40% of the power going through them. To save you the math, four conversions at 70% efficiency leaves you with a fraction over 24% of your original power. So to put it another way, you have to generate four times as much power as you need. And in the real world the numbers are much worse than that.

Small scale local generation, preferably from renewable sources, is the only way to reduce these inefficiencies.

Patrick Brinton