Should clean energy be distributed energy made locally and connected to a smart grid, or should it be gathered from the windiest and sunniest places on the planet and shipped to us in giant new super grids? The answer may prove critical to solving our greenhouse gas problems.
Unlike our federal highway system, which is needed to transport goods across the country, or the “information superhighway” of the Internet, which is the fastest way to carry information around the world, long-distance transmission lines have no inherent value. On the contrary, the farther electricity is transported, the more of it is dissipated. “Line loss,” as this is called, gobbles up an estimated 2 percent to 3 percent of electricity nationally.
And of course, the longer the power line, the more expensive it is to build. In New England, we estimate the cost per mile at $2 million to $10 million. The closer electricity is generated to where it’s used, the better.
There are many benefits to building a smart, distributed energy system. One problem with distributed energy is that is people don't necessarily live where clean energy resources are most abundant; another is that wiring together many different parts can impose regulatory costs that could make deploying distributed energy more difficult, and can be a hassle for homeowners (one of the reasons various schemes to rent or lease people home solar power packages remain popular).
That's why some smart folks argue for putting the power generation where the power resources are and then building a new international grid of transmission lines to carry that clean energy from wind farms and solar fields to distant cities. The model of centralized production and distant consumption suffers particularly from the "line losses" of electricity wasted while transmitting it. One possible solution is the "ultra high voltage" direct current power line, which delivers large amounts of power over long distances with relatively little power loss.
It's not a perfect fix, since there are both technical problems (like the conversion of that direct current to the alternating current used in homes and businesses) and cost issues (it's expensive to build big infrastructure, no matter how efficient). Still, China is planning 15 long-distance UHV lines while there is growing support for a plan by the European commission's Institute for Energy to use UHV lines to build a "super grid" to bring Saharan solar power to Europe. (You can wonk out more on transmission options here.)
Given the severity of the crisis we face, when presented a choice between two approaches to providing clean energy, the answer must be "both, please." But in this debate, as in every other, there are trade-offs, and it's worth thinking about when we want our volts local, and when being hooked into the super grid makes the most sense.
Photo: Wind farm in New Jersey. Photo credit: flickr/iirraa, Creative Commons license.
This is a fascinating point of contention. For one, I must give credit to the fact that it is being debated at all- it shows that, at the very least, people are thinking in a forward fashion in relation to energy consumption/distribution. Another high point is that on either side of the argument, its still assumed that energy will be generated by clean sources.
Personally, I cannot decide which method would ultimately prove to be more resilient in the face of disaster. Locally produced energy would be ostensibly the better choice, as it can distribute impact more. No matter how super your grid is, if you lose your solar field, you still loser that source of power generation. (Presumably systems would not rely on just ONE input for each area.)
On the other hand, there is the technical challenge of maintaining local generators. I consider myself a DIY kinda person, but I don't want to be responsible for maintaining a component of my city's power generation. At the very least, local government if not state government should be involved in maintaining a standard of power output per household, otherwise the potential for system decay becomes a dangerous possibility.
In the end, I presume, as stated in the main article, a bit of both is advisable. Frankly, I'd take either just to advance the system in the first place.
I also predict that the "both" approach is what will happen, with the majority of the emphasis on local generation (and if there is no/insufficent local source, as a society we should really question whether people should live there - but that is another topic).
IMHO a key part of this strategy is to develop a roofing material/materials that produces electricity, heats water, and does not look like it was installed by NASA. There are a few photovoltaic roofing products available, but I have not seem them widely used. Also of course, roofs on new homes should be designed to optimize solar gains.
Personally I would like to see all south, east and west roofs used for solar gain (some combination of photovoltaic, hot water, and room lighting). The north roof should be a "green" roof, i.e. plants.
I don't think this problem is that difficult to solve:
- PV shingles/slates that both look good and produce electricity at a reasonable efficiency/cost. Every building has a roof anyway, so maximizing efficiency is not as critical as say at a solar power station in the desert.
- Solar hot water shingles/slates that match the rest of the roof.
- Relatively simple and robust connections to the home wiring and hot water system.
- Smart connections to the grid. If you pull from the grid, you pay (debits). If you push to the grid, you get paid (credits). If there is more supply than demand (or grid capacity), gate the supply. If there is more demand than supply, either increase the "imported" supply, use local supplemental sources (neighborhood storage, generators) or reduce the demand (smart appliances/electric panels? Incent people to reduce demand?), or both. We are used to "unlimited supply" but I think it would be good for us to be a little more in tune with nature and the ebbs and flows of resources over time.
i wish that there was more talk of connecting efficient public transportation to new energy systems
I'm an electrical engineering student whose been considering these ideas seriously for a while now. Good analysis overall. I would just like to emphasize that the solution is probably not either-or with centralized v. distributed clean energy, its both. The nuts and bolts and ratios that are most desirable will change from place to place. For now be happy when you see either type of project in your neighborhood.
It is probably the case that select progressive communities will lead the way in providing local energy and they'll do it light years ahead of how long it will take the federal system to come on-line. On the other hand, the rest of us probably need a national system...
Wouldn't it be nice if individuals could sell an unlimited amount of power to the new grid systems at market rates. Then a homeowner could opt to invest by purchasing solar panels or wind turbines for excess energy production and resale rather than taking that money and throwing it down the toilet into the stock market. Making it easy for a homeowner to sell electricity would also dramatically decrease his energy consumption because he'd want to sell it rather than simply leave the lights on all night.
Germany has a feed-in tarrif system that encourages property-owners to invest in solar power production. It works pretty well for them. The net-metering arragement here in northern California is good, but the rules are designed to prevent small producers from investing to make money. As to the benefits of local production, Amory Lovin's book "Small is Profitable" covers it pretty thoroughly. We will undoubtedly have both central and local power production for a long time, but I hope we end up shifting more towards local production--it just makes more sense.
A good solution may include both local and distant generation. We probably shouldn't commit to a final solution in this dynamic context. A reasonable strategy would be to start with local generation and see how far it takes you. At the same time, aggressively reduce the demand and waste.
As local generation proceeds, materials technology will likely advance. As a previous commenter noted, that will make local generation even more effective -- possibly even obviate the need for distant generation.
The idea of decentralized electricity production sounds smart and I am all for it. However, there are two drawbacks: First is storage and second is maintaining the monopoly (of utilities, regardless who owns them) Both can be solved. Storage of electricity is not yet solved in an economic way. However, when you produce hydrogen direct from real renewable energies like (concentrated) solar, wind, hydro power even geothermal in a new, not yet existing process (without going over electrolyses and without going over reforming fossil fuels). You can store the decentralized created hydrogen also decentralized (at your home/office/grocery store or at the filling station) and then use it to cook, heat, cool, drive and have all your electrical appliances working on. Monopolies are not always a good thing. They tend to use their monopoly to their own (systematically) benefit, not necessarily to the benefit of their customers. We all have examples of such a behavior.
The basic idea is simple: "Power to the people". At the 2008 Fuel Cell Seminar in Phoenix, AZ, I presented this idea in a poster:
Locally generated power sounds great and all, but I don't see how it can realistically replace a large amount of the current power usage. Especially if there is any large-scale switch to vehicles that get power from the electric grid, which significantly increase demand.
Assuming your goal is to continue to meet current levels of demand, how do you get enough power from local, non-fossil fuel sources to power New York City? What about San Francisco?
Relying on local power, at least with current technology, seems like it would only work for small cities in the sun-belt or great plains.
Powering big cities probably involves a gradual shift towards high-efficiency buildings, PV, combined heat and power, and importation of renewable energy from surrounding areas. New York has the potential to harvest some power from the river flows (East River and the Hudson), and tidal, wave and wind along the coastline. Every city has something, whether it's sun, wind, waves or geothermal. Each locality will have to come up with its own mix of efficiency and power generation.