The US DOE seems to suggest that the “manufacture results in toxic pollution” angle is somewhat overblown.
I’m not a solar skeptic - I think solar power has made great strides and could very soon become a viable power source.
But it’s not going to be base-load power. A 10,000 square mile solar plant would be horrifically expensive - not just to build, but to maintain. There are zillions of connections, valves, pumps, motors, you name it. 10,000 square miles of that kind of stuff would be an engineering project of a scale we’ve never seen before. And I suspect that 10,000 square miles gets a lot bigger when you consider how much room you need to move equipment around, get vehicles in and out, etc. Then account for the percentage of sections that will be down for routine maintenance or repair.
But cheap solar could wind up on rooftops, in plants for remote towns, as supplemental power for malls, factories, schools, etc. Solar car covers for electric cars would help charge them while they’re parked at work. That sort of thing. All together, it could make up a sizeable fraction of our energy use. But it won’t replace the need for large amounts of concentrated power available on demand.
How easy is it to rapidly ramp up manufacturing capacity for solar PV cells? How much capital, time and technical expertise is required to build the manufacturing facilities themselves? I am not sure whether this could be a potential bottleneck - even if a cost effective method of manufacturing exists, can we build the facilities fast enough? I honestly don’t know whether this is much of a factor.
I see that the Scientific American plan targets having 3000 GW of solar PV capacity by 2050 - that’s something around 75 GW increased capacity every year if it was spread out evenly. According to this abstract, global solar cell production was 3.623 GW. Obviously solar manufacturing will have to grow exponentially for several years to meet these goals. At what point do we start to see diminishing returns on reduced manufacturing costs due to increasing scale? Do we have enough engineering and construction resources to design and build these manufacturing facilities in the timeframe necessary? Working in the Alberta oil sands business when oil was $140/barrel, I have seen what occurs when there is significant scheduling pressure combined with a shortage of construction resources - skyrocketing costs.
Then you have to wonder about the lower limit to the cost of a unit of production. Increasing the scale of manufacturing should help reduce unit costs to a point, but will the availability of materials become a prohibiting factor to increasing the scale of manufacturing? According to this article, silicon is currently the limiting factor but it appears silicon manufacturing is taking big strides. Looking at this, it appears that an estimate for silicon plant costs are $250 million to provide silicon for 50MW/year worth of solar cells* - seems like this would be $5 billion for each GW/year increase in solar PV capacity. They also peg $1.30/W (so $1.3 billion/GW) for the solar cell manufacturing itself. To increase to 75GW/year manufacturing capacity, it would appear we would need $375 billion in silicon plants and $97.5 billion in cell manufacturing plants or $472.5 billion in capital cost required - and I’d be very surprised if you could bring on 75GW/year of manufacturing capacity just like that. In any case I agree that $400 billion seems like a rather optimistic estimate.
Still, I think the potential is there for solar. I have a feeling that solar thermal has more immediate growth potential than solar PV. I don’t understand the electrical grid well enough to know how difficult grid integration will be for solar systems - I know that it has been one of the big hurdles for wind power growth here in Alberta.
*Actually upon closer examination it doesn’t actually say how much silicon a $250 million plant produces - it does say that the cost of polysilicon factories will DWARF the investment into solar cell manufacturing facilities, so maybe even more capital will be needed?
Let me know when anyone is talking about covering ten thousand square miles with any other sort of electronics. Even if the amount of pollution per square meter or whatever is small, when you’ve got numbers like that, it really adds up.
Oh yeah. The actual electronics (that have toxic byproducts) in your computers and things are relentlessly small. This would be orders of magnitude huger.
Actually, though, the big problem with solar is that power generation cannot be dependant on it. We have to be able to ramp up power production arbitrarily to meet demand at that exact second, and that puts limits on it. Solar can help, but that’s it.
- Keeping the pollution issue in perspective.
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While some do dream of a network of solar and wind farms connected by HVDC and with energy stored such as by putting water up into resevoirs, the practical side is smaller but more vital. Distributed solar can provide energy when it is needed most, during peak times, allowing for less spinning reserves. Essentially the idea is that solar is giving extra supply when demand requires it most. Distributed solar can also locate that additional peak capacity near where it is needed helping avoid overburdening transmission infrastructure. (And the need to invest in improving it.)
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As far as ramping up to meet to meet short term increases in demand, allow me to point out that nuclear generally does not either - it is used as base load power and is on or off.
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My thought: power companies, especially ones that rely on coal plants currently, will need to do something to reduce their carbon costs. I foresee them paying rent (perhaps in the form of discounted power rates) to factories with bigflat roofs in areas of poorer transmission infrastructure in particular, and using those roofs to place distributed solar generation that they will sell to the company and use to offset some peak needs in the substation area. The electricity generated then is the electricity most costly to them and decreasing peak demand marginally has the biggest payoff if it also spares their overburdened infrastructure.
[quote=“DSeid, post:26, topic:488170”]
- Keeping the pollution issue in perspective.
That misses the point entirely. Air pollution was never the worry.
Probably not. Peak times tend to be when solar power becomes unreliable, i.e., morning and evening, when half the year it’s dark or fading light. It could help in the business day, but only as far as taking a little of the edge off the top.
Key word there is “air”. Fossil fuels pollute the air more, but that doesn’t rule out the possibility that solar panel production pollutes the water more.
For those interested this is an amazingly good review of the subject.
Per that cite, no very little water pollution. But lots more in there for the interested reader.
Do you have a cite for this? My understanding has been that while power does spike in the mornings when people wake up, peak power usage is still when they’re getting to work and powering up all those computers and what not (and running the aircon like crazy in the summers.)
Would it not be better to have the solar panels scatters thru out the area rather then one massive site? Assuming we can figure out workable transmission system, would it not make more sense to just for sake of argument put solar panels on the entire roof surface of ever house in whichever state has the best/most sunlight, no likely widespread natural disasters. and then wire those to the assumed transmission system. Surely then it would be easier to maintain it, as faulty panels could be reached easier and isolated. A couple of specialists in each town to monitor them etc. This would also help prevent a utterly crippling terrorist attack, one EMP would black out the country and bankrupt it. For example, if you placed solar panels atop every gas stations canopy. Which would return power the local houses/businesses everyone wins, and you turn useless space into a advantage, no-one would even know they were there. One look at google maps, and you can see how much potential space there is for the taking in this way.
I would also assume that each state would have its own natural resource to take advantage of whether it be wind,solar or water. So would it be better to focus each state on its own resource and build a plan on that. Would that not reduce cost as you would not be required to build a infrastructure for the whole country, but each state by town?
With a price tag in excess of 420 billion a year, I do wonder if you just started at one end of the country and worked house by house, adding solar panels to each one, with no connecting infrastructure, how long would it take to make every house in the US energy independent. If there was a serious effort by the government and we all worked together, i bet we could do it faster than 2050.
As a final word, i do fully support the the X-prize idea by ITR Champion
In cold climates, I imagine the power spikes in winter, at night or when there isnt much sun in general, or when its cloudy becasue its cloudy and cold and snowing.
Peak and troughs vary in different communities and during different times of the year. The numbers seen in this somewhat critical of solar site are pretty common for what I’ve seen before:
(As the graph of Winter demand shows, from the morning rise until the late afternoon/early evening bump it is pretty level, as is your understanding.)
That last bit, about how it the peak is more towards the middle of the day in the Summer, is a key bit. Summer is when demand peaks seasonally, often almost twice as high as during off-season. All that air con like you suggest. That’s why Summer always brings us rolling black-outs and brown-outs mid-day and in the afternoon. So during peak seasonal demand time solar as a resource best matches peak demand - providing its complementary electricity production just when it is the most valuable, more clustered in middle of the day and there amply during that afternoon peak time of day during the peak season - and if distributed locally then also sparing the transmission infrastructure by being where it is needed.
(bill, imagination is good - but data helps too. :))
It’s not my experience that people actually use electricity for heating in particularly cold climates (fuel oil being particularly common in the northeast US), so I’m not sure this is true, but if you have any actual data, I’d love to hear (see) it.
Btw, that seasonal peak link is an interesting site for other reasons. It points how how expensive managing those Summertime daytime peaks are. The perspective there is not from the POV of adding the supply by solar, but how valuable it would be if that demand could be shifted some. You’d
Of course the same benefits plus would be accomplished by providing that 5% of peak demand when it is needed with solar… making it a more attractive item for the power generation companies to consider in the next few years.
DSeid, the cite is much appreciated. They’re both fairly long pages, so I expect to take a little while to really even skim through them, but I didn’t want you to think I was ignoring you.
Of course you need ELECTRICITY to run ACs (not really but most people do it that way).
Too keep warm in the winter, most folks instead burn evil fossil fuels.
You try to substitute electricity for burning of fossil fuels and cold winter nights are gonna spike like hot summers are.
Data is good - but critical think skills help too 
What are you talking about? You’re the one who said that power spikes in cold climates at night. DSeid and I called you on it, and now you’re trying to invent some hypothetical counterfactual where we replace burning of fuel oil and natural gas with electricity use and claiming in that scenario we’d see the spike you talked about? Where’s your evidence even for this claim? Who’s to say the power use at night from heating wouldn’t just be offset by all the lights and machines that are off during that time (why power usage is lowest at night now)?
If you want anyone to take your claims seriously here, be clear about what you’re claiming, provide some evidence, and stop accusing others of lacking critical thinking skills.
bill I also am totally confused trying to follow whatever point you are trying to make here.
The conversation here is about the place of solar power.
The relevant issue regarding peak demand is that currently the most expensive electricity is the electricity produced when the system is reaching over its capacity to produce and to transmit. Having the ability to meet those peaks requires an overbuilding of supply side and meeting those peaks produces incredible expense. The greatest peak demand is daylight hours during Summer especially in warmer areas of the country like the Southwest. That happens to be the when solar is the greatest resource and the where solar is the greatest resource.
Now if you want to talk about heating homes in Winter in the Northwest then that is a different conversation. Natural gas (not that evil as far as fossil fuels go) is likely to remain a good bet there although certainly new construction homes can take advantage of a variety of passive solar techniques and good energy conservation like adequate insulation and good windows.
My link even did support your claim some: in Winter it is true that electric heat being turned on contributes to a bump as the sun goes down. The counterpoint was just that daily peak electricity demand in Winter is still not what stresses the system or costs the most - peak Summertime is.
I think that your most recent strawman is trying to argue against solar as a replacement for all other power generation in the US, all other electric generation and natural gas for heat as well. If so then let me be very clear that I know of no one who is arguing that solar has that role. Even those who point out that that 100 mile per side square taking up 9% of Nevada could power all of the US if filled with concentrating solar thermal electricity generation at a current cost of $0.13/kWh are not proposing that such a megaplant be built. But if solar electricity is used to displace the need for as many peaker plants and to decrease the amount of spinning reserves, then it is competing with electricity that costs the power companies somewhere between $0.25 to 0.40 to produce, and again that’s the time that solar is at its best. Solar will be a cost competitive and significant part of the mix, especially as carbon is actually priced.
There’s an analysis demonstrating that photovoltaic solar power can’t make a net contribution to our total power generation for at least 30 years, because it takes power to manufacture the cells.
The cells produce more power within their lifetime than it took to make them, but it takes something like 3 years to hit the break even point. If you want to have photoelectric contribute more to our total power generation, you have to keep increasing the production of them. Going faster invests more power in them at first, and going slower takes longer to have a big contribution. The briefest period to reach net contribution was 30 years.
At least, this is what I remember of it. I did read that Scientific American article, but I don’t think that’s where this tidbit was - I think it was in the Economist a couple years ago.