Monday, May 16, 2011

Why Big Solar is a Bad Idea

I came across this article and thought it had some interesting points...your thoughts?

Ten Reasons Why Decentralized Solar is a Better Idea
Of late there has been much talk about moving towards a solar energy future. This is a positive development (albeit one that is almost too late) and has been driven, no doubt, by recent studies that have shown that solar and wind power are now amongst the cheapest forms of power generation, several critical breakthroughs in related fields, and big moves by some major players. However, it seems that a lot of money is being thrown at a particular type of solar power plant; massive centralized solar plants. It is my opinion that this is a massive mistake.

We have an opportunity to build a new power system to replace our failing grid with something more resilient, more efficient and more egalitarian, and if we don’t take this opportunity we will be stuck with mild changes to the old system. I feel that big solar is actually a real threat to our future, or at least our best possible future, and we need to focus a bit on it now before the form of our electrical system is set in stone.

In fairness, centralized solar does have a few benefits, so let’s start with them before I explain why a decentralized system would be a much better choice.

1. A centralized solar plant requires fewer engineers and workers to build and maintain the solar power collectors than a distributed system, on a per megawatt basis. This means there is less up front cost, and you employ fewer people. I guess that might help the stock price, since Wall St. tends to invest against employing people.

2. A large solar installation, or better, many of them spread across many states, provides a consistent money stream for the plant owner, especially after the upfront cost of the plant is paid off.

3. A large solar installation can take the place of a coal or nuclear plant, providing energy without the many downsides of the older technologies.

Notice anything about these benefits? The first two are primarily beneficial to the plant operator, and not to the community that the solar plant is in.

1. A decentralized solar collection scheme is far more energy efficient than a centralized one. More than 30% of our electricity is lost in transmission in our current system, and a centralized solar plant is no different than the current system in this way. A decentralized system can supply power to where it is needed directly most of the time, only using the grid to offload surplus power.

2. A decentralized solar strategy will employ far more people per megawatt than a centralized one, employing small businesses and technicians to maintain and install systems wherever they are needed. We really need jobs right now, so this should be a big selling point.

3. A decentralized solar system will be far more resilient to natural disasters, as there will be no single points of failure that can bring down the whole grid, as there is with centralized power generation. Do you remember the blackout of 2003? A bad solar storm could be far worse.

4. A decentralized solar system utilizes unused space on rooftops and in yards to generate power, whereas a centralized system requires the development of new land, destroying habitats while generating no more power. Indeed, given the amount of unused roof space in the US, you could completely solve our energy issues by covering only a small fraction of it with solar collectors. Add solar collectors built into roads and pathways, and we have all of the space we need to solve the energy crisis for good without clearing any more land.

5. A decentralized solar strategy gives power to the people, in more ways than one. Since the people are generating electricity, they are also generating capital continuously in the form of free electrons. The result is that the community is made richer across the board, by producing a useful, valuable commodity directly under the control of middle and lower class people.

6. A decentralized solar strategy provides market space for lots of technologies to compete directly, without the generally anti-competitive nature of big monolithic construction contracts crowding out the small players. In the short run, this will provide more opportunities for small businesses to grow. In the long run, this enriched competition will produce a more efficient and refined product.

7. Rooftop systems shade the structure underneath, cutting energy usage in the summer months. This is an additional energy savings above and beyond the major issue of transmission losses.

8. A decentralized solar collection strategy preserves a place for things such as solar water heaters, which are a much more efficient way to heat water than generating power miles away, losing a significant portion of it by shoving it through wires, and then heating more wires to heat water. The difference in efficiency for this one task is enormous.

9. A decentralized solar strategy doesn’t require huge governmental loan guarantees to get off the ground. It doesn’t require government help at all, though it would be nice if local governments would get out of the way and let people set up these systems without bureaucratic hassles or ridiculous energy buy back schemes. If the government gets involved, it could be in the form of rebates or tax abatements, which are proven to be a more effective way of distributing public funds into the economy than big monolithic projects. Or it could be in the form of innovative projects that use the acres of rooftops on civic structures to generate power instead of just more heat. Even if you are utterly skeptical of governmental action, you could just think of it as a handy way of reducing the hot air coming out of your local legislative bodies, while finally putting them to some useful work.

10. This one is often missed: the secondary costs of a centralized power system, like beefed up transmission lines, large ugly transformer stations, and so on are rarely calculated into the cost of concentrating lots of megawatts in one place, but all of those expensive accessories are going to have to be paid for somehow.

What about wind? Well, it turns out that wind generators work best when they are spaced out generously, and so the laws of physics are already working against a whole lot of centralization. Many of the early attempts at a highly centralized wind generator were a failure because the closely packed mills created turbulence that reduced efficiency and in some cases caused damage. The closest things out there are some very successful county projects, but in those cases people in rural areas rent out a parcel of their own land for the windmill to be erected on. It works, it’s easy money, and it’s out of the bag. You should assume that everything I am arguing for here can work just fine with all of the wind power we can muster.

Of course, we can’t expect people to build a complete power system themselves. There still needs to be some large scale investment in such a system, and I think there is money to be made while strengthening our communities. A number of corporations, like Boeing, have already seen the value in investing in a form of power that is not tied to the fickle winds of international politics. Decentralized power requires an investment in regional and local power storage devices to hold extra power generated on windy or sunny days and release it back into the system on less active ones. The thing is, our current system really needs such a capability too, as even there is energy lost in off-peak hours by idling generators. Soaking up some of that electricity cheaply and releasing it in peak hours could be a profitable business even now. However, for some reason, I can’t fathom getting financing even for mature and dependable alternative power systems, like geothermal, is extremely difficult. Correcting that lack of foresight on behalf of the credit issuers might require some loud complaining by a lot of people. Indeed, the work that is needed to correct a wide variety of outdated policies is the a greater barrier to the widespread adoption of alternative energy than any technical challenge.

All of the problems that we have with our current, decaying electrical system will need to be fixed, unless we care to look forward to a future of power shortages. It’s going to require a lot of investment, no matter what. We can try to hold together the old system with stopgap measures, but the inherent inefficiency of transporting electricity over long distances simply can not be corrected. If we all take the initiative, we can break up the system into something that is more flexible, and sustainable. One that can stand up to trouble in a way more like the internet than a house of cards. And one that will pay off it’s greater upfront cost by sharing the load of that cost better, and paying off bigger in the long run. But we all have to understand what is at stake, and that positive change is going to be opposed by people who would rather build new monopolies than give (electrical) power to the people.



Michael Boxwell said...

You make some interesting points, many of which I agree with. However, I personally think that we need both centralized and decentralized solar energy as they actually do two different things.

Right now, these big centralized plants have solved one of the biggest issues with solar energy - they incorporate a large scale energy store allowing electricity to be produced from solar around the clock. This is a HUGE benefit and means that we now have a genuine alternative to coal and gas fired power stations.

The build cost of these big stations is far lower, per kilowatt-hour, than smaller systems. This means we can replace coal and gas fired power stations at a lower cost and provide electricity at a lower price. Economics do the rest: coal-fired power stations become too expensive to run and the big power companies have a stark choice: build solar power stations and produce emissions-free power or go out of business by burning coal. That's a no brainer.

You have exaggerated transmission losses. This 30% transmission loss figure is an urban myth: the true figure is around 7½%, of which 1% is with the long distance high voltage lines and 6½% is the lower voltage system from the substation. If you are proposing smaller, local area power stations, you're still going to be getting a 6½% transmission loss from the 'final mile' transmission. In effect, there is very little difference in efficiency in that regard.

However, there is a greater efficiency from the bigger power stations than the smaller ones - and this difference is huge. Instead of using PV, these big stations are using thermal energy to power a turbine. I am told tht efficiency levels at the moment are around 20% and projected efficiency levels in ten years time will be around 40% - better than efficiency levels from current coal or gas fired power stations.

Personally, I think we need both centralized power and decentralized power: there is a balance for both. We already have the infrastructure for centralized power, and the cost benefits of this technology could force the industry to go green - whether they like it or not - through simple economics. Where there are small peaks of high electricity demand, small local power stations can take the stress, with community based power stations and individuals providing power from their own solar roof systems.

wouldnt care less said...

Decentralised is best, in everything, people need to make a living somehow, if only a few make a living who the heck is going to buy their merchandise and on what?
Decentralised is best since centralised is easy to hit by a small team and thus disrupt power for many, but it takes an atomic bomb to destroy a whole city that is all roofs solar self powering system, thus terrorism is useless and powerless against decentralised.


Peter Lilienthal said...

You only alluded briefly to the greatest benefit of decentralized power: reliability. MOst outages are caused by disturbances in the distribution system, so distributed power is the only way to provide the highest reliability. Once electric vehicles or other electric storage devises become widely available everyone can be responsible for their own reliability.

You also mistook the real problem with long distance transmission. The losses are trivial, as someone else pointed out, but the costs and permitting difficulty is substantial. The cost is particularly problematic if new transmission is being built just for renewables with a 20-40% capacity factor. The permitting issues may be completely intractable, but at a minimum they will take years to decades to overcome. Finally, the promised miracles of the smart grid are only practical if implemented through micro-girds first.