You could read my post …
Agreed. This is a snapshot of one particular point in time and solar is an area that is changing rapidly and which may (or may not) change much more. It is not mature technology.
I’m not saying it is watertight but here is some interesting reading
So we have the “real cost” figures for everything except solar. And natural gas has suspected higher costs than the official calcs plus it is likely to run out very quickly if its usage is ramped up. Where’s the figures for solar?
It’s worth considering. I do workers comp for a living and roofers are a b**ch to insure. Some companies won’t even take them.
Work comp claims affect the business’s bottom line and is certainly front-loaded into the cost of installing rooftop solar power. Stricter workplace safety with regards to roof work, which we as a country do need, will add more expenses to the cost of rooftop solar energy - but again, this is an automatically up-front cost because a business would be flat out stupid not to pass the cost of workers comp premiums onto the customer.
I don’t know that the costs of solar are what I typically here being complained about either, (to echo Der Trihs.)
When it comes to any sort of energy there is really a triad of issues and for some reason in most discussions about energy these issues will frequently be confused with one other, partially addressed or ignored, and essentially muddled.
I posit when looking at a source of energy there should be three primary concerns (not ranked in any particular order):
**Expense / Unit of Energy Generated **- Important because this is ultimately going to be what consumers and industries pay when their utility bills come do. Prohibitively expensive energy sources will seriously harm consumers and industry, destroying jobs as industry is forced to lay people off and reducing spending as a large portion of household budgets go towards home energy bills.
Pollution & Environmental Impact / Unit of Energy Generated - With pollution the per unit amount isn’t always as straight forward. For example with nuclear opponents insist you must factor in, to a degree, the potential negative consequences of disasters like Chernobyl or Fukushima. Since there will always be valid debates about how to quantify potential pollution, that makes this a more difficult to pin point metric. Most people will agree that coal is the biggest offender pretty much across the board when it comes to pollution. Oil is pretty bad too, but in the United States at least oil fired power plants are a part of our history at this point.
Natural gas power plants are generally viewed by all parties as being cleaner than coal or oil; some say natural gas has greater potential impact in its extraction process versus coal (I don’t agree at all, but I’ll note the argument for fairness sake.)
Nuclear, sans disasters, is generally agreed to be cleaner than the above fossil fuels. Solar, Wind, Geothermal, Hydroelectric…and any other renewable energy sources I have not named are all argued to be cleaner than nuclear and also argued to not be cleaner than nuclear (it depends on who you’re talking to. Opponents of solar of course will mention disposal costs of panels, opponents of wind will talk about dead birds, opponents of hydro will talk about damage to local environments from damming up rivers and etc.)
**Scalability - **How well can this technology be scaled up? There are many sources of energy that work great on some levels but not on others. Powering a personal vehicle? Gasoline is great, there’s a reason it became the gold standard. Powering a power plant? Gasoline wouldn’t be a great option. Heating a home? Both fireplaces, wood-burning stoves, and wood-chip fed furnaces have been and are used to heat homes, very economically on an individual level. Wood-burning power plant? Not so great, especially when you consider the implications and how much wood you’d need on a global scale for that level of energy generation. Wood burning power plants of course do exist (although generally as more generalized biomass burning power plants.)
When talking about scalability you are not only talking about how well it can scale up, but how well can it scale up without causing environmental problems? Coal scales up great, and its environmental problems scale up with it. Wood burning, based on some information I’ve seen, actually produces more pollution than coal, so even advocating its use to power home furnaces may be of questionable use environmentally.
With solar my questions are always going to revolve around the third issue, scalability.
I haven’t studied solar extensively but I know that:
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A certain amount of energy is available from sun light per square foot (or meter) of land. It will of course vary based on geography. The amount goes down to essentially nothing when the sun is no longer shining. This amount of energy is far less than the amount that hits the sun up at the edges of Earth’s atmosphere, by coming down to the Earth much of that energy is lost. Even assuming we catch all of it where we are collecting it, how many square feet of the Earth’s surface will it require to meet our current energy needs (let alone future energy needs.) Unless then answer is like “400%” or more, then there’s no hope of solar being a complete solution to our energy needs.
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My understanding is that solar panels only capture a certain percentage of the energy striking the area in question, essentially saying solar panels are only so efficient. My understanding is that while newer panels are being developed all the time, there is some theoretical limit to how efficient they could be. Like I said, I’ve not researched it. I have heard that using mirror-arrays to focus the sun’s light actually allows a greater portion of the sun’s energy to be captured than any solar panel systems, if that is true I would say that we shouldn’t be focusing energy on solar panels but instead on advancing the mirror technique.
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My understanding is that a huge portion of the earth’s resources would have to be devoted to the infrastructure involved in large scale deployment of solar. This obviously can make the technology prohibitively difficult to utilize.
Now, all that being said, any argument about the future of our energy that relies on “one energy source” just won’t work. The truth of the matter is if we’re going to make it for the next few hundred years we need to dramatically diversify.
That will even included some utilization of technologies that are somewhat more expensive per unit of energy than coal, because we have to start regarding the full costs of energy creation which will cause society to judge coal as being too expensive to continue using at the scale it is currently deployed. We will also need lots of consumer-level changes and technologies. Home geothermal heating, home solar panels, more efficient cars.
Solar and wind aren’t suitable for all areas, and can’t be relied upon for a significant portion of your energy needs. To begin with, solar power doesn’t work at night. If you want solar to be your energy source, you need to somehow store a half of days power. We are no where near being able to do that, and likely never will. Thus, as backbone power generation solar is out. That doesn’t even begin with the problems of places like New York which have cloudy and overcast winters. What it all boils down to, is that you need to have almost 1:1 duplication of your solar generating capacity. Obviously that’s a huge cost.
Wind is better because it works at night, but it isn’t 100% reliable either. Are you planning on shutting down everything when the wind stops? And what are you going to do about the places without enough wind to generate sufficient electricity?
That is what it comes down to me for wind and solar. They are fine at reducing emissions by allowing us to turn off fossil fuel plants while the sun is out or the wind is blowing. So yeah, they may be cheaper on a per GW, but if we are talking about hidden costs, you need to include the necessary redundant power generation.
Solar has the advantage of not requiring a huge plant be built. A home owner can drastically cut his fossil fuel use and sometimes go off the grid. The cost is his . The community does not have to be involved unless they give a tax break. But the tax payer also gets a break. Fossil fuel demand drops and the pollution is diminished.
Are you doing it, then? Are you off the grid and using solar on your house to meet all your needs? :dubious: Me, I live in a place that gets ridiculous amounts of sunshine pretty much all year long. And I actually DO have solar panels on my roof. And it doesn’t come close to meeting my energy needs, even though I have energy star compliant appliances, double paned windows and extra insulation on my house.
To use solar effectively you DO need a huge power plant…one that’s many MANY acres. And then you need an infrastructure to get that power back to the grid so it gets to folks who need it. And then it only works when the sun is out. And, of course, such a power plant takes quite a bit of maintaining to keep it working at optimal levels.
Seriously…what do you and the OP think? Let’s pretend for a moment that solar IS the cheapest and bestest form of energy. Well…why isn’t anyone using it to make all their clean energy dreams come true, if that’s the case? Why is anyone (besides us evil Americans, controlled by Big Energy(aar)) still building any other kinds of power plants? Why build coal, why use fossil fuels if solar can meet all our needs?
Easy answer…because it can’t. In order to make solar competitive you’d need to add a lot of costs onto coal or other fossil fuels. Obviously, that’s what you and others are trying to do…to add the costs of coal and ffs impact on the environment to the cost of the energy. And that’s fine…it’s impacting us all, it kills thousands or even 10’s of thousands each year due to respiratory ailments and the like, and it’s definitely impacting our environment. But at least be honest about the discussion. Solar can’t compete unless someone makes coal cost a lot more than it costs now…and that means that energy in general is going to cost a lot more. Which is going to have it’s own real world impact, and will probably cause some non-zero number of deaths due to that alone. Then, of course, there is the actual environmental impact of putting up hundreds of square miles of solar panels on the environment…or the human cost of putting the things on peoples houses and the inevitable deaths that will be caused b that. Then there is the impact from manufacturing.
All of this is being ignored by the OP, of course because, well, it wouldn’t be Le Jac without ridiculous oversimplifications and over the top pronouncements.
Why do people continue to say and think that fossil fuels are cheaper than solar? Because that’s the reality. Not only does solar not scale up to the levels that fossil fuels do, but it simply costs more than anything else…unless you give it a boost by making everything else cost more first. Then it wins at least the cost side of the equation, even if it still doesn’t measure up to the kinds of scales of energy we require to make a modern nation function.
-XT
Not in that cite anyway. Again, solar is a work in progress. Maybe after the DOE’s Sunshot initiative has had a chance to bear fruit it will be worth calculating. Even without that initiative prices are dropping. Again however PV has its manufacturing wastes already monetized and disposal at end of life? I can’t find numbers for it. Concentrating solar is making progress and there is little waster during its life. Costs of making the mirrors and all? And of disposing of it at end of life? I would guess minimal but have no numbers.
CSP has the advantage of being able to use thermal storage to provide reliable baseload power day and night.
Basically we don’t have realistic figures yet for large scale solar applications.
Boring old silcon photovoltaics are a mature technology which is great for powering satellites and calculators and electronic devices remote from any grid, but horribly expensive for large scale power generation. There may be a technology revolution in photovoltaics that will change that (there’s certainly plenty of “breakthrough” stories in the news) but nothing that anyone has turned into large areas of collector and stuck out in a desert.
The alternative to photovoltaics is thermal solar, using mirrors or lenses to focus the sunlight and generate power with a heat engine. There’s many different designs and a few experimental plants such as Andasol in Spain. The cost of the thermal solar energy is currently very high, but this is probably because nobody is mass-producing and churning out thermal solar power components in the same manner as wind turbines. Large scale solar is in its infancy.
A resources-used analysis based on the Andasol plant can be found here which shows that solar power at Andasol requires 15 times as much concrete and 75 times as much steel per megawatt as nuclear. Wind by comparison requires about ten times as much concrete and steel as nuclear. Solar is going to have to do a lot better that that before it becomes viable. One weakness of renewables is the relatively low area density of the power, requiring large area constructions to collect the energy. I’m already concerned that wind power installation will run into a wall as steel demand rockets, and if solar requires 7 times as much steel as wind then it won’t go anywhere. This despite being an energy resource several times denser than wind and far more predictable.
Andasol is not the only pilot plant technology and I’d love to see a similar analysis of the Suncatcher stirling engine system, for example.
http://www.stirlingenergy.com/pdf/2010_01_22.pdf
You don’t generate solar power locally to consumption. You generate it in the desert where land is cheap and insolation is high, and use high voltage DC lines to send it long distance. You can also use solar to generate hydrogen and pipe it across continents, or store it for peak generation. All this requires a fundamental reworking of current infrastructure, of course.
One of the technologies the Andasol plant is testing is on-site power storage in a heated molten salt mixture. Andasol can store 8 hours worth of power generation as hot molten salt and there is no reason why this can’t be scaled up. It should also be noted that night-time power demand is very much lower than daytime.
Martin,
The sum of Expense/Unit Energy plus the Pollution & Environmental Impact/Unit of Energy Generated is what we have been discussing.
Scalability is often fallaciously claimed to be a point against renewables; it is not, and precisely because renewables are not a single answer, but as you correctly point out, a diverse portfolio of answers that complement each other and that are part of a toolkit that can be applied in various circumstances. Biomass, including wood, fares extremely well in lifecycle analyses. If you have data to the contrary please offer it up. Otherwise invite our biomass for electricity expert Una to make some comments. Or just search for her past posts on this subject. There are issues in scaling it up to be sure, and she has shared those with us before, but it could be yet another part of the answer. Meanwhile I’ll merely offer this cite.
matt,
Solar can be and often is generated on factory rooftops. It can be produced in utility grade sites and it can be produced as part of a distributed generation system both. It competes with peak demand electricity for those applications. If a consumer in my local ComEd region uses real-time pricing peak power can cost more than 4 times as much as trough electricity.
Interesting, but what do you mean by “trough electricity?” Are there commercial parabolic trough systems for rooftop mounting?
The opposite of peak. Electricity produced at times of low demand, usually in the middle of the night.
One modest example of rooftop solar.
A factory can be operational 24/7 with rooftop solar providing anything from a portion of its peak daytime needs (and saving it that much daytime peak price electricity) to oversized for its daytime needs, selling excess to the grid during that time, and buying back from the grid at night (trough) when the grid has cheap surplus capacity.
A related concept is utilities leasing rooftop space. The unifying idea here is that the most valuable electricity is daytime peak electricity. Distributed systems that spare the transmission and generating infrastructure its marginal costs during that time of the day are worth more than the average price of electricity.
:smack: Should have been obvious. That’s what I get for thinking in only one context.
I don’t know even close to enough about biomass power generation to argue the point. I was really just using a common fuel many people use in their homes (wood logs) and saying you probably can’t scale that up to society wide levels. My understanding is a biomass power plant is using more dense and easier to transport forms of biomass then the big bundles of logs you buy for a fireplace.
When I was arguing that wood burning power plants would not scale up as well I was only basing that off the fact that of course a log of wood is a less dense form of energy than coal. Bulkier fuel source means vastly increased transportation costs, and I’d be interested in seeing what supplying 60% of the world’s energy from wood alone would do to things like home prices and et cetera (if in fact it’s even feasible.)
In any case I tried to differentiate true “biomass power plants” from “large power plants modeled after a fire place” because I don’t know anything about biomass power but I do know that just creating a big massive fire place and throwing huge logs into it all day to generate heat to use for electricity generation is without me needing to do much research almost certainly not a very efficient or scalable energy solution.
I’m not really interested in clarifying the point. So instead of even talking about wood, let’s replace that example with say, hand-crank powered flash lights or portable radios. Those have their uses but no one is advocating we put a bunch of Egyptian-pyramid builder-esque slaves to work manually generating power on a societal scale.
That still doesn’t solve the problem of night. Besides, we are talking about technology and infrastructure decades away, if possible at all.
Well the hydrogen kind-of DOES, if you use daytime electricity to produce it by electrolyis and then use the electrolysis cell in reverse as a fuel cell to generate electricity at night. And yes, the storage technology may be decades away. Nobody is going to retire fossil fuel overnight, or even over the next few decades. However, wind is teetering on the price-point where it can beat coal, at least on paper, and solar should have the capability to do the same. If there’s money to be made, it will develop. You also missed my cite for Andasol being able to generate for 7 hours of darkness by using heat stored in molten salt. That’s technology being trialled NOW, TODAY, and it can be scaled up just by making the salt storage tanks larger.
[rul=Scientists Invent Solar Cell Sheet That Collects Energy at Night]Not true anymore.
This has already been achieved.
As cited above, you can collect energy at night with technology that just came out.
Two words: transmission lines.
The tech to nullify the problems you mentioned has been invented and some of it is already in the wild, with the rest on its way.
Oh, snap! I was just citing the Andasol example. You beat me to it.
As for the concrete and steel requirements, now that’s astounding. How does it compare to coal and oil? It looks to me like the real costs fight narrows down to solar vs nuclear.
IIRC correctly, coal needs a little less concrete and steel than nuclear, gas combined cycle needs much lower than anything else, and I’ve never seen figures for oil. Oil isn’t used for power generation much.
I think you’re right about it coming down to a choice between solar and nuclear in the long term, with wind ending up being quite limited, but at the moment solar is coming up too expensive. There are signs that modular, mass-produced concentrated solar is coming onto the market though. The Tessara Suncatcher stirling dish is one example, with an impressive 30% peak efficiency: Blog énergie - Le guide sur l'autonomie énergétique de la maison I couldn’t find any details as to how much steel and glass goes into each dish. They look quite sturdy.
For concentrators that don’t use much in the way of resources, Cool Earth Energy has a design for inflatable concentrators - see http://www.coolearthsolar.com/technology . Unfortunately they don’t seem to have much more than a concept - the website’s been up for years and I’ve yet to see even a photo of a real-world prototype yet. Green and gold energy’s Suncube tracking fresnel lens PV concentrator OTOH is in production and has gone international. http://www.greenandgoldenergy.com.au/