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Post by anonposter on Mar 17, 2013 1:52:43 GMT 9.5
I guess nobody wants to build stuff with a negative EROEI, I do, synthetic production of hydrocarbon fuels must have a negative EROEI. I've also heard talk about using nuclear reactors to provide the energy to get difficult oil (e.g. tar sands) that would take more energy to drill for than it would produce when burned. If we cover 1% of the world in solar panels, we are going to need 1% of the world as landfill for those panels 25 years from now. No, landfills can be three-dimensional and the old panels would probably be recycled (assuming anyone was stupid enough to try it on that scale). Still a lot more landfill volume required than with the nuclear option. The energy to mine the bauxite and iron and rear earths, and smelt the steel and aluminum, and manufacture and transport and emplace and operate and maintain and decommission and dispose/recycle today's solar and wind systems exceeds their lifetime energy outputs and costs. PV panels do appear to produce more energy than is used to make them, though when you account for the fact that the power they supply the grid isn't very useful it could be argued that they are actively harmful by their mere presence (still not as big as the harm they cause by diverting attention away from nuclear). When solar and wind power have progressed to the point where they can provide the power density to run mines and smelting plants and manufacturing facilities and remelt the glass and aluminum and steel and re-crush and re-kiln the concrete, then we will have something. You could run a factory on solar power, just that unless you're in orbit you wouldn't want to. Until then, this is just a big, expensive circus being pulled by the locomotives of oil and gas. Make that coal and methane, oil is barely used for electricity production. |
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Post by geoffrussell on Mar 17, 2013 16:38:37 GMT 9.5
Some people seem to confuse the sun with solar power. Solar power is not forever. PV solar is a system of hardware with a finite lifespan--generally 25 years or so--that degrades in performance over time. If we cover 1% of the world in solar panels, we are going to need 1% of the world as landfill for those panels 25 years from now. The energy to mine the bauxite and iron and rear earths, and smelt the steel and aluminum, and manufacture and transport and emplace and operate and maintain and decommission and dispose/recycle today's solar and wind systems exceeds their lifetime energy outputs and costs. That's why those costs have to be federally and state subsidized, and shared across utility customers and taxpayers and investors, and hidden in complex funding schemes involving future RECs and undisclosed PPAs. The O&M contracts for many of these installations have already changed hands more times than a Countrywide liars-loan mortgage. When solar and wind power have progressed to the point where they can provide the power density to run mines and smelting plants and manufacturing facilities and remelt the glass and aluminum and steel and re-crush and re-kiln the concrete, then we will have something. Until then, this is just a big, expensive circus being pulled by the locomotives of oil and gas. The problem with EROEI calculations is that its very difficult to capture the chain of inputs. The best way to do such things is with I/O analysis as in "The Balancing Act" www.csiro.au/Outcomes/Environment/Population-Sustainability/BalancingAct.aspxThis enables you to include in the cost of your solar thermal power (with storage) everything from the mirrors back to the mining of the metal used to build the trucks to carry the steel used to build the chemical factory to make the salts for the storage etc etc. The whole incredibly complex chain. But even that isn't enough when you start to scale a technology in such a way that marginal capacities get broken. For example, build 4 solar plants and you don't need any additional trucks in the system, the transport just chews up bits of slack. But build 8 and you may need more trucks, which won't have a function after the plants are built. How does an EROEI calculation handle such situations. But solar PV or thermal stretches our logistical capacity in complex ways. A big nuclear build would stretch it also, but in fewer fundamental ways. We simply wouldn't need to move as much stuff. |
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Post by sod on Mar 17, 2013 19:44:36 GMT 9.5
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Post by cyrilr on Mar 17, 2013 20:47:08 GMT 9.5
So Germany does not get power from solar for 94.4%. After hundred billion dollar money throwing. That is not encouraging, but for some reason solar enthusiasts such as Sod are very happy at not solving problems 94.4% with energy sources that are not there 90% of the time, at 100 billion euro price tags. Did you know Germany is the world's biggest consumer of brown coal? That's the dirtiest type of coal, if you didn't know. If we all follow Germany's policy, world CO2 emissions will quadruple in no time. Don't worry, be happy. Put solar panels on your roof and feel good. |
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Post by anonposter on Mar 17, 2013 22:42:37 GMT 9.5
I wonder: is there any countryside left in my country? will i starve, because we can t grow any food any longer? There isn't enough land in Germany for renewable energy to meet your needs. What this means is that Germany has 4 options - Draconian rationing of energy (bye bye first world standing of living)
- Import energy from elsewhere (better hope the supplier is a friendly country, like say, France)
- Burn fossil fuels (once other countries get serious and start imposing carbon tariffs while correctly ignoring how many shiny black panels and bird blenders…)
- Split Uranium (idiots won't like it)
and where are all those trucks? Where the renewable energy facilities are being built and on the route between the factory or port and the site. |
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Post by sod on Mar 17, 2013 23:00:52 GMT 9.5
Germany is getting more electricity from (non-hydro!) renewables now, than it does from nuclear. en.wikipedia.org/wiki/File:Electricity_production_in_Germany.PNGBut the country is not covered by wind masts and solar projects. The artcile is overestimating the problems by far. The WWF got it right. I am sorry! PS: "watch c-beams glitter" was the solution for the security check. It is the most entertaining version of such a check, that i ever encountered! |
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Post by cyrilr on Mar 17, 2013 23:51:29 GMT 9.5
Duh! They've been pestering, blundering, and taxing nuclear in every possible way for decades!! You are no doubt very proud of that. First regulate and pester a viable industry (nuclear power) to death, then subsidize an industry that will never ever be viable (grid connected PV in Germany) with 600-700% subsidies, and then you claim that PV has achieved a lot and nuclear has not? That's the most pathetic and disengenious argument I've heard in months. The simple fact that you can't understand is that France got to 75% nuclear in 15 years, whereas Germany has barely 6% solar in 20+ years of blind money throwing. That is not conjecture. It is reality. It happened. We should learn from Germany's failure and France's success, rather than cheering at failures while time ticks away. The reasons are pedantically simple. Solar has a capacity factor of 10% in Germany. Nuclear gets 80% in France. It means that a nuclear Watt in France produces 8x as much electricity as a solar Watt in Germany. Since nuclear plants last 2x as long as solar plants (60-80 years versus 30-40 for solar PV if you're lucky) it follows that the nuclear Watt in France produces 16x as much electricity as the solar Watt in Germany. These are simple facts. Draw your own conclusions. |
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Post by anonposter on Mar 18, 2013 3:59:32 GMT 9.5
Germany is getting more electricity from (non-hydro!) renewables now, than it does from nuclear. But does that electricity do any good? If they are backing it up with fossil fuels then there is minimal reduction in fuel usage and hence CO 2 emissions. But the country is not covered by wind masts and solar projects. Because Germany hasn't even come close to powering the entire country on renewables. It's been calculated what it'd take and there just isn't enough land in Germany to do it (Europe as a whole couldn't either). For Australia or the US the energy does exist so the problem then is the whole massive overcapacity and need for a weeks storage along with the environmental impact but for Europe and Germany in particular it doesn't. The artcile is overestimating the problems by far. The WWF got it right. I am sorry! They looked at the entire planet and indeed we're not a K-I civilisation yet (though I want us to become one, somehow I doubt you do) and found that there is enough surface area to meet the entire planets needs if it were all spread out. Densely populated areas have a lot more people per surface area than the average for the Earth so there can indeed be regions on the planet which can't get by on their own renewables. |
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Post by edireland on Mar 18, 2013 12:52:20 GMT 9.5
But the country is not covered by wind masts and solar projects. The artcile is overestimating the problems by far. The WWF got it right. I am sorry! Using known figures for average UK annual insolation and the known efficiency of monocrystalline silicon solar panels (the only ones that will ever be available in sufficient quantities to provide significant maounts of power at the grid scale), an estimate of the area of photovoltaics required to produce the average energy demand of the United Kingdom can be derived. Current average grid load over the year is about 40GWe. This can easily be expected to double if natural gas is phased out and with our expanding economy, giving us ~80GWe. MacKay (who I don't agree with on many points related to nuclear fuel availability) has derived an estimate for an entirely electrically powered UK vehicle fleet that shows a requirement of roughly ~26GWe. This takes us to somewhere in the vicinity of 105GWe. The average annual insolation in the United Kingdom is ~900kWh/m 2. This translates to an average power of roughly 0.1kW/m 2. Which means, even if storage is perfect and has no losses, with ~15% efficient solar panels (used in the WWF solar "Atlas") you would only generate roughly 15MW for every square kilometre of solar panels. This means you would have to cover something approaching 7000 square kilometres with solar panels. Assuming the entire area of the site is a continuous sheet of solar panels. Once a 20% derating factor (again lifted from the WWF Solar "Atlas") has been included to account for access roads and shading avoidance this figure rises to 8400 square kilometres. That is roughly 3.5% of the United Kingdom's entire land surface. On the face of it that doesn't sound too bad, until you realise that is approximately 15% of all the United Kingdom's arable land. If you attempt to put all these solar panels on rooftops this area will increase to be greater than the entire developed area of the country as it stands today. If you attempt to move the solar panels to areas not intensively used for arable crops you will end up with an average insolation figure that could be 15% or more lower than the one I have used and still displace animal husbandry related farming activities. Either way you intend to consume rather large amounts of valuable farmland. This is just absurd, and you can't use wind power as a getout for this because the amount of wind turbines you would require to provide this power would lead to the average number of turbines visible from any point in the UK being something over a hundred. In comparison to generate 105GWe of average load using modern ESBWR type reactors you would need roughly 115GWe of installed plant, which is roughly 75 reactors. That is approximately 12 Gravelines NPP equivalents (the reators are larger but the plant would have a similar footprint overall as the reactor and turbine hall is only a small part of the plant's area). This would translate to six square kilometres. Which is probably far less area than would be covered by the concrete supports for all those wind turbines or solar farms. |
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peterc
Thermal Neutron
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Post by peterc on Mar 18, 2013 16:54:30 GMT 9.5
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peterc
Thermal Neutron
Posts: 30
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Post by peterc on Mar 18, 2013 16:58:52 GMT 9.5
BTW, thank God for mathematicians. The few remaining folks who can still add, subtract, multiply, and divide might be our only hope for salvation. As MacKay famously said, it's not that he's in favour of nuclear, but he is in favour of arithmetic. |
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Post by Soylent on Mar 31, 2013 19:56:32 GMT 9.5
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