Grid or No Grid?
A recent comment on one of my posts suggested that having one's home off-grid was the only "green" option. That troubled me, partly because it goes against what appears to be common sense. To me, it appears logical that if I produce power when you need it, and you produce when I need it, then the total production capacity need not be as great as if you and I each have to cover our total needs. Thus, the potential use of green production (not only solar but wind and hydro) is maximized. A grid powered entirely by green energy would seem to be far more efficient than a hundred million or more individual generating systems isolated from each other.
(This principle has been applied with small "Dendro" power plants in South Asia: a single plant is shared by several homes rather than each home getting its own unit, which would be more expensive and less efficient.)
Interestingly, a former Clinton Department of Energy official said something similar, commenting on the country's first "hydrogen-powered home." Let me first say that I think the technology shows great promise, and I wish our government had had the foresight to develop this technology years ago. As it is, a civil engineer in NJ was the first to build it. The principle is that excess solar energy generates hydrogen, which is stored and used to generate electrcity using a fuel cell when the solar panels aren't operating at peak capacity. Unfortunately, according to the article, the process of generating hydrogen from electricity, then generating electricity from hydrogen, is only 50% efficient. Half the energy is lost in the process. I'm sure technology can improve the efficiency given enough time. According to Joseph Romm, formerly of DOE, [quoting the article's explanation of Romm's position] "that electricity would do more good toward reducing pollution if it was sent into the main power grid to displace other energy." So, at the very least, there seems to be some disagreement about off-grid being greener.
(This principle has been applied with small "Dendro" power plants in South Asia: a single plant is shared by several homes rather than each home getting its own unit, which would be more expensive and less efficient.)
Interestingly, a former Clinton Department of Energy official said something similar, commenting on the country's first "hydrogen-powered home." Let me first say that I think the technology shows great promise, and I wish our government had had the foresight to develop this technology years ago. As it is, a civil engineer in NJ was the first to build it. The principle is that excess solar energy generates hydrogen, which is stored and used to generate electrcity using a fuel cell when the solar panels aren't operating at peak capacity. Unfortunately, according to the article, the process of generating hydrogen from electricity, then generating electricity from hydrogen, is only 50% efficient. Half the energy is lost in the process. I'm sure technology can improve the efficiency given enough time. According to Joseph Romm, formerly of DOE, [quoting the article's explanation of Romm's position] "that electricity would do more good toward reducing pollution if it was sent into the main power grid to displace other energy." So, at the very least, there seems to be some disagreement about off-grid being greener.
This argument is for the status quo. As long as more demand is placed on the grid, utilities will build more coal plants, creating more pollution. If you have the resources to generate for your use, alleviating the demand on the utility grid is the way to go. Otherwise, you are partly to blame for the new plants.
Having an independent power system while still connected to the grid just says you want the dependability of the utility without the guilt... and you're not willing to take the steps that individuals with the means should take.
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Sorry, Kevin, the more I read and reflect, the more I disagree. Blaming the distribution system for the source is like blaming roads for the existence of SUVs. Roads existed long before the internal combustion engine, and will likely exist long after internal combustion gets retired to museums.
Then there's the matter of practicality. Consider: our monthly usage last summer (July/August) averaged 480 KWH. With some reduction, we could forseeably generate that much in 16 hours of daylight. But in December and January (our highest months of consumption), our usage averaged 1,045 KWH. Generating that in an 8-hour solar day would require a 5-fold increase in generating capacity-- capacity that would be wasted the rest of the year. On our budget, that's not just undesireable, that's impossible.
In addition, the grid makes possible the economy of scale. Imagine if the "off-grid" solution was projected to over 100 million homes and businesses nationwide. Kevin argues that can't happen-- which begs the question of how practical it really is and how much impact it can have. Still, project it out as far as imaginable. Not only would it waste energy due to the inability of each system to share or store excess capacity, but it would also create an artifically high demand for components, driving up price and reducing availability. Suppliers report that some components are frequently on backorder as it is. Maybe I'm missing something, but I don't see how a widespread "off-grid" solution helps maximize solar's impact on the problem of fossil fuel use.
We're trying to do the best we can with what we've got. Do we want the security of the utility? You bet we do, and for as long as possible. In January, (before our system was fully operational) the utility failed for a few hours, and our pipes froze, leaving us without water for a week. On solar alone, we could have kept the pipes from freezing for those few hours. But over the course of a winter without utility power, we'd have to choose between running water and keeping the chickens from freezing to death. If we ever do lose the utility, we'll be talking about a nationwide reduction in quality of life, and bringing the chickens into the bedroom won't seem so bad.
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1-"Roads existed long before the internal combustion engine, and will likely exist long after internal combustion gets retired to museums. "
The movement toward federally funded highways in the 40s and 50s is exactly the reason we have the light duty fleet that we do. Roads are the reason for White Flight and urban sprawl. To argue against that is to deny established history and sociology. Roads had to be improved because of the automobile too, or the impact of the vehicle would not have been realized. A trip down Colonial Williamsburg brings this to light.
2"Interestingly, a former Clinton Department of Energy official said something similar, commenting on the country's first "hydrogen-powered home."
This is actually a false claim as a university had already built the first solar home that stored energy as hydrogen. It was in competition in D.C. a couple of years back. If you want to see the cutting edge of home solar technology, the Solar Decathlon is an excellent place to start.
These are the facts: If you are connected to the grid, with a solar system or not, you are connected KVA. You are potential demand. DJ lives in Utah and should know about the 950-megawatt coal-fired plant being proposed near Delta. There are also 11 planned coal plants for Texas alone. Removing connected KVA for utilities is the only way to remove their argument that they need to produce more power by building more plants. By being potential load, you assist your utility in making arguments for coal plants.
The analogy I make is being a subscriber to a newspaper. By getting a physical paper, you contribute toward the pollution and logging that goes into making it. If you read the content online, you have not reduced your impact to the environment, as you are still a subscriber. You can defend being a subscriber all you want, and then try to couple the fact that you actually read it online, but it does not make sense. The only way you reduce the paper's circulation of a physical paper is by not buying it/not subscribing to it. Same thing with being on the grid...
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I do see some merit to your argument. The highway analogy works to a point, but the newspaper analogy doesn't convince me. Based on your various comments, I'm becoming convinced that the problem is not demand, but politics. If all energy going into the grid was green-sourced, then the grid would be green as well.
Using your argument, how many homes/businesses "off grid" would it take to make a difference (in either demand or politics)? A hundred thousand (less than 0.1%)? A million? Ten million? Al Gore is working hard just to get 350,000 signatures on a petition. Is it realistic to get this many homes off-grid?
Still, assuming you're correct, installing enough generating capacity to cover our needs, even if reduced in all reasonable ways, would cost more than a year's annual income for us at the curent cost of compenents and installation. We thought we were doing well to do what we've done. Where does the rest of the money come from?
This, ultimately, is the problem with individual greening: most people just can't afford it. Every individual can make some contribution according to their means and situation. But becoming green must be structural, else only the rich will accomplish it-- and we will all suffer the consequences of the failure of the rest.
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Kevin, I'd like to invite you to share the details of your own off-grid system: what are its components, how much did it cost, its projected cost recovery, and whether you modified systems and/or behavior to make it work. If you have photos you'd be willing to share, let me know and I'll put it together as a blog article. Thanks.
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1 "Using your argument, how many homes/businesses "off grid" would it take to make a difference (in either demand or politics)? A hundred thousand (less than 0.1%)? A million? Ten million? Al Gore is working hard just to get 350,000 signatures on a petition. Is it realistic to get this many homes off-grid?"
The grid does not work that way. It is distributed, meaning that green technology being adopted in one circuit would not alleviate it in another. They are connected which helps prevent adjacent grids from collapsing. An example would be when you contribute solar energy to the grid. It could impact your neighbor (in that he would use the power you generated), but it would have little impact across town on another circuit. So a number is relative... as little as a thousand 'green' households would have a considerable impact on some substations but little on others.
2- " We thought we were doing well to do what we've done. Where does the rest of the money come from?"
I really didn't intend to come across as an attack the incredible step that you did take, even though there was probably no other way in getting my point across. I would say in your case, as well as anyone without generating capabilities, look to conservation. Timers on water heaters, lights. Smaller, more efficient refrigerators. I myself have adopted a vegan diet and I have no need for anything larger than a college dorm sized refrigerator (energy star of course)
3-Kevin, I'd like to invite you to share the details of your own off-grid system: what are its components, how much did it cost, its projected cost recovery, and whether you modified systems and/or behavior to make it work. If you have photos you'd be willing to share, let me know and I'll put it together as a blog article. Thanks.
I'm an electrical engineer employed by BP Solar (formerly Solarex). I go through different components all the time but I am not allowed to go into detail about most of them until release dates. I am, however, more than willing to post about systems I have installed/and will install in Kenya and Cambodia with Engineers Without Borders. The papers I have already written about those experiences are very technical and may be dry to some.
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