Next Generation Energy is managed and written entirely by Seed editors and expert guest bloggers. Read more about them Before oil prices began to soar, before 'global warming' became a familiar phrase, and before nuclear power was even dreamed of, people were harnessing the energy from the sun for their own purposes. It is rumored that the ancient Greeks used bronze shields to concentrate solar rays and set fire to their enemies' wooden ships. Solar-powered steam engines were around by the 1860s, solar cells not long after, and in 1921 Albert Einstein received a Nobel Prize for his work on the photoelectric effect. Indeed, any discussion of alternative energy as recently as ten years ago—outside of certain scientific circles—would have revolved primarily around solar power.
Solomon Hsiang said in his first post, "Since almost all of the energy available on Earth comes from the Sun, we should probably think about how close and how simply we can connect ourselves to that power source." And the methods we have found to do just that have developed and expanded greatly within recent years; both solar thermal and solar electric technologies have become far more efficient and cheaper to build. A report issued by publishing company Clean Edge and Co-op America (an environmental nonprofit) estimated that solar power would become cost competitive with oil by 2015, if not sooner.
So, what are the technologies that will take us to this point? Does the answer lie in photovoltaics, in thermal collectors, in concentrating solar power? Will we eventually be able to rely on solar power alone, despite a push for a diversified energy infrastructure? And of course the obvious question—what are the downsides?
Environment
Comments
What I like about solar energy - especially PV - is the whole no-moving-parts bit. Especially if you want home generation, that looks a lot lower maintanance than either wind power or even CHP.
IF you could get a situation where installing a 'solar roof' became not much more expensive than normal re-roofing, you could get a situation where all new buildings and renovations had significant generation. Not just mounting a few solar cells on the roof, but making it structural.
That requires 'cheap and rugged' over very high efficiency.
The advantages? Probably not overall cost; but you are looking at security of supply (keeping the freezer cold in an outage), and daytime electricity demand tends to be higher than nighttime, so there could be some genuine peaking unit displacement. Disadvantages? Cost.. and would enough electricity be generated to make it useful overall?
Posted by: Andrew Dodds | August 13, 2008 9:27 AM
I've been preaching the "Since almost all of the energy available on Earth comes from the Sun..." thing for years.
Of course the issue with PV is the cost. A national program to double efficiency and halve cost is one of the most worthwhile projects I could possibly imagine. Unfortunately, as a non scientist, from the outside looking in, it seems there is no truly coordinated research towards these goals.
Based on the literature I've read I believe it's possible to heat a house through the winter in almost all areas of the U.S. What's lacking here is a national effort to educate, and offer incentives to home builders.
I see frame houses going up all the time with more efficient building methods ignored. Here again education and incentives would help move the country towards better building methods.
Einstein, along with Leo Szilard, patented a closed loop, absorption based, refrigeration system requiring heat as the power source. With no moving parts this device could theoretically operate for centuries with no maintenance. Research to determine if this type of cooling system could be operated by solar thermal panels would be another worthwhile investment. Adsorption chillers are even more efficient than the absorption chillers in common use. Perhaps a ground coupled adsorption chiller run off the heat of solar panels could air condition the next generation of houses in the world.
IMHO only a Manhattan Project or Man on the Moon type effort will get us the results we need in a timely manner. I can only hope the next president will be intelligent enough to realize this and take action.
Posted by: Connie Keeling | August 13, 2008 10:05 AM
That bit about the Greek warriors is bunk.
If we're going to make solar work, we've got to tackle the price. It needs to be made as cheap as possible, as quickly as possible. There is simply no reason most cars couldn't have an adapted solar system to "help" re-charge their battery(ies). Combined with a hybrid system, this seems the next crucial step.
In addition, why is no one talking about a hybrid vehicle, like a Prius or something, that runs on E85? When Indy switched to 100 percent ethanol (denatured, but basically with high-octane racing fuel) they saw superior mileage, and realized many efficiencies. It only makes sense to do something like this and combine it with solar technology.
Posted by: Flippin | August 13, 2008 11:34 AM
Depends on what you mean by "useful". I used to live off-grid, with a very small PV set up (like about 1.5 m2), which was enough to run TV, radio and lighting, even after a month of heavy overcast and continuous rain. Sure, it was never going to run a freezer or a washing machine, but I'd say it was useful. Plus you get the great fun of popping round to the neighbours only to find that they're sitting in the dark because of a power cut that you were completely unaware of...
Posted by: Dunc | August 13, 2008 11:37 AM
What, you mean like the Ford Escape Hybrid E85?
Posted by: Dunc | August 13, 2008 12:08 PM
Yes, and where do you buy one, Dunc?
Posted by: Flippin | August 13, 2008 12:09 PM
You said "talking about", not "selling". These things do not happen overnight. Not that I think E85 is a particularly good solution anyway, given the problems with producing the ethanol.
Posted by: Dunc | August 13, 2008 12:15 PM
"It is rumored that the ancient Greeks used bronze shields to concentrate solar rays and set fire to their enemies' wooden ships."
... well, that myth was busted pretty thoroughly by Adam and Jamie. Even with precision mirrors in an aimed array, they couldn't set fire to a floating, tarred wooden boat nearby.
Posted by: ouini | August 13, 2008 4:23 PM
Dunc -
I'd refard having a fridge and freezer as pretty essential, as well as a washing machine. But there again I have around 32 square meters of suitable roof..
Assuming I could average 30W/m2 for 8 hours a day, that would mean 0.24 kWh/day/m2, or ~7kWh/day. Wikipedia puts domestic annual electricity consumption (non-heating) as 5000 kWh/a or ~ 14kWh/day.
The Wikipedia estimates seem quite high (140W for lighting, which in my case means practially every light in the house..).
I wouldn't be able to go off-grid because you can't run an electric cooker of of that size PV array, or batteries, realistically. But it would be a useful contribution, and is all generated at times of high demand - at least in the UK, the lowest demand is from 11pm-5am. That's pretty important from a coping-with intermittancy perspective.
http://en.wikipedia.org/wiki/Domestic_Energy_Consumption
Posted by: Andrew Dodds | August 14, 2008 4:02 AM
Good Lord! My electricity consumption currently averages 3-4 kWh/day - and that's with a fridge freezer (small, admittedly), washing machine, dedicated beer fridge, electric oven, an all-valve hi-fi system (that does a not bad job as a space heater), and a brewing boiler. I use gas for the cooker hob, heating and hot water. I do live in a pretty small flat, but I think that helps put into perspective just how significant a contribution you could make.
Even if I spend the whole week at home, with the PC and the hi-fi on all day, and do two 5-gallon brews, my electricity consumption is still less that 10 kWh/day.
Posted by: Dunc | August 14, 2008 5:36 AM
When Indy switched to 100 percent ethanol (denatured, but basically with high-octane racing fuel) they saw superior mileage, and realized many efficiencies. It only makes sense to do something like this and combine it with solar technology.
Posted by: karınca yumurtası yağı | August 14, 2008 3:00 PM
I wouldn't be able to go off-grid because you can't run an electric cooker of of that size PV array, or batteries, realistically. But it would be a useful contribution, and is all generated at times of high demand - at least in the UK, the lowest demand is from 11pm-5am. That's pretty important from a coping-with intermittancy perspective.
Posted by: Zayıflama | August 14, 2008 3:01 PM
Yeah the greek solar 'death-ray' is bunk. But the Romans in North Africa did build very efficient 'sub-level courtyard' houses. When archeologists first ran across the ruins, they were all wondering why there were nice mosaic floors in the basement... well, if you live in a hot climate and are clever you spend the day in the basement. (Actually, basement is not the proper term, since the most common design had a central courtyard open to the sky... 'basement' denotes a claustrophobic aspect that doesn't fit.)
Which brings me the the actual point. Our main 'source' of new energy over the next several decades should (hopefully will) be not using the energy in the first place. There is basically no negative 'living standard' impact for the vast majority of efficiency measures... we are just too wasteful and short sighted to actually use them.
Bringing me around to France and Nuclear Power. Pro-nuclear power folks keep saying that France gets 90% of their power from nuclear. True, but in relation to US consumption, France gets ~50% of their power by not needing to use it in the first place!
Once we actually get serious about efficiency, solar (and all sorts of other methods) become real options. Don't buy into FUD like "we would have to cover the entire Mojave Desert".
Posted by: travc | August 20, 2008 11:21 PM