225

The Guardian cites a 2010 study that found: the average windfarm [sic] produces 20-25 times more energy during its operational life than was used to construct and install its turbines. It also found that the average "energy payback" of a turbine was 3-6 months. Wikipedia has a graphic that is based on another 2010 study showing similar numbers: The ...


218

This study, by a nuclear advocacy group, is based on treating a cubic meter of used solar panels as being equivalent to a cubic meter of spent uranium. Just digging around the links, I find the following: Yes, slashdot's description is pretty accurate. "Environmental progress" is a pro-nuclear advocacy group. The website initially presents as a general ...


90

The number claim is correct in the context of nuclear power stations. The "440" reactors from the claim indicate, that we are talking about nuclear reactors for power generation in power plants. Therefore I won't include reactors used on submarines or vessels. According to the International Atomic Energy Agency (IAEA) there are currently (May 2019) 452 ...


84

Can the US be powered by a 100 x 100 miles solar grid? Desertec is basically the same idea, solar plants located in North Africa supplying power to Europe. The article includes a map showing the area required to power Germany, Europe, and the whole world, respectively, as estimated by the German Aerospace Center (DLR). That estimate puts 100x100 miles for ...


83

If it replaces coal mining for power production, fracking reduces CO2 emissions, but that's not the whole story. Burning anything results in increased CO2 emissions, and methane leaks in fracked gas infrastructure result in CO2 equivalent emissions that erase the gains in reduced CO2 emissions compared to coal. Engel's argument rests on two key assumptions ...


53

Quick Take: There doesn't appear to be available information to determine if the coal plants were burning coal, although not contributing electricity to the grid; there is sufficient information to say that the coal plants were not exporting electricity out of Great Britain. It looks like the event actually included all the coal-fired power plants in Great ...


51

Red flags: As Kevin points out, 20kW from a 200W panel is PFM (Pure Frelling Magic). Significant portions of the press release are dedicated to how strong the patent is. No patent number is given. The landing page of the site is the press release. The banner for the site is "Breaking News", making the entire site effectively a giant press release. ...


34

No, The Register has misrepresented the story. There are several parts to this question. The summary is: "Peak Wind" is a myth: there is nothing similar in wind to how hydrocarbon stocks will get to such a depletion point that annual production will decline inexorably thereafter. The modelling methodology smackdown - Have previous estimates over-estimated ...


29

First, let's agree on definitions. Fracking (or hydraulic fracturing) is a process by which fluids are drawn from the ground. In this context, the fluid would either be oil or natural gas. From the article that you link: Engel’s resignation letter said: “The UK is currently spending £7bn a year on importing gas – money that is not being used to ...


25

In 2012, there were 437 nuclear reactors. From the World Nuclear Association: Over 115 commercial power reactors, 48 experimental or prototype reactors, over 250 research reactors and several fuel cycle facilities have been retired from operation. Thus, if just 1.5% of 850 reactors (or 13 reactors) suffered a meltdown, over 1.5% of nuclear reactors would ...


23

It seems possible, at least in theory. Of course, whether it possible and whether it's remotely economically feasible are completely different questions. A decent back-of-the-envelope series of calculations here shows that 10,000 square km of solar panels could provide more energy than the US uses. This was in response to the same (or at least a similar) ...


22

One red flag that's pretty clear in the diagram on the site is the hydrogen storage aspect. A 200 watt solar panel isn't going to power an entire home all day. Adding a device to split the water into hydrogen (and oxygen), eRET(?) requires additional electricity. Simultaneous hydrogen storage while powering the entire house is an absurdity. The eRET ...


20

Do wind turbines kill many birds each year? In short: An upper estimate might be of the order of half a million birds per year in the USA. However it seems that hundreds of millions of birds are killed by collisions with other man-made structures. So wind turbines account for a small percentage of bird deaths attributable to human activity. Nevertheless ...


19

No. Nuclear energy produces far more toxic waste than solar. Distribution of the fake news story The fake news that began circulating at the end of June 2017 stems from a self-described "study" conducted by the nuclear industry advocate, Environmental Progress (EP). James Hansen, a nuclear proponent previously a lead in climate modelling at NASA, has ...


18

Given there's much talk about the 2010 study, here's a 2013 one. It mainly expand the other one, by: "Tweaking the lifetime": very low ones were assumed for conventional plants (also including deprecated centrifugal enrichment tech for nuclear) "Counting all output", even if not needed: i.e. including the need for buffering (aka "backup" in case of variable ...


18

It is certainly possible to "harvest" power via induction from high voltage power lines. There is a vertical voltage drop from the wires to the ground. This effect can power stuff. For an example of this, see this (awesome) picture of a neon being lit by proximity to the power lines. source Also, this energy leakage is openly admitted by power lines ...


13

The simple answer is yes. The more complex answer is that the number of deaths is nothing in comparison to other man made structures and the risks from climate change. There have been several studies done to find the environmental impact of wind farms on birds. Generally birds lack the ability to dodge humans and their quest for global supremacy. From the ...


13

The question cites two links, but neither of them raise as a claim the question of how long it takes for a renewable energy system to recoup its energy cost, which is the title of the question. First I'll address the very broad question in the title, for which no notable claim was cited (but which will exist somewhere out there). The two links cited raise ...


11

40kW out of a 200 Wp solar panel? 200 Wp (Watt-peak) is the nominal power of the solar panel. It means that the solar panel produces 200W of power when the module has a temperature of 25°C and is under an irradiance of 1000W/m². See "standard test conditions" in IEC 60904-3. At night, a 200 Wp panel produces exactly 0W and during a cool, sunny day, the ...


11

No, the claim is faulty on both parts Using the US Geological Survey report on Estimated use of water in the United States in 2015, we quickly see that the original claim that thermoelectrical power-plants consume the most water is not correct. Table 2A shows that thermoelectrical power plants do withdraw 133,000 Mgal per day, and that is on par with ...


11

Not impossible, but highly unlikely The technology described does exist. Scientifically this is called Plant Microbial Fuel Cell. However Bioo's claims of 40 W/m² seem greatly exaggerated. People involved in e-Plant, a Dutch company which already has similar product on the market have published a number of scientific papers in Biotechnology for Biofuels ...


9

This blog post has a detailed analysis of the deaths from various forms of energy. It would seem to agree with the result of a large number of deaths saved from the use of nuclear energy. For just air pollution it says: The World Health Organization and other sources attribute about 1 million deaths/year to coal air pollution. Coal generates about 6200 ...


8

No, the claims are completely untrue. The science of why is a little complicated. The opinions of the users of Physics.SE are that it is: improbable to the point of being gibberish. The opinions of the users of Quora are: The obvious problem with Mills theory is Hydrinos don't exist. It's 99.99999% chances to be a scam. [...] What we are looking at ...


8

Unsurprisingly, given that it is from the Heartland Institute, it appears to be wrong. Looking at 2018 government data (note: Excel file), electricity generation in California is 30% greater in July (air conditioners?) than in September and October. So a 10% or even 17% drop in generation capacity should not create a shortfall in supply, as long as there ...


7

Their claim is that currently nuclear power saves close to 80,000 lives annually. It's true, that WHO attributes 1.2 mln deaths to outdoor air pollution. So at first glance numbers makes sense. Nuclear power is 6% of total, 6% of 1.2mln is 72,000. Close enough... or not? Their fallacy seems to be believe that all pollution is equal, and all pollution ...


7

The figures seem consistent with most sources: A Lazard 2018 study puts nuclear firmly in that range. A UK government study puts new nuclear construction at 95 GBP per megawatt hour, which sits somewhere in the middle of the range stated by Reuters, depending on the exchange rate of the day. The OpenEI configurable chart trends lower, but only outliers lie ...


6

The roi depends on the windmill, and it could be bigger than 3-6 months. For example, if the windmill operates in colder regions, "the additional cost of such a system [de-icing] can be compensated by additional production within 2-3 years of operation." Source http://www.elforsk.se/Global/Vindforsk/Survey%20reports/12_13_report_icing.pdf Of course, a wind ...


6

An answer to this question depends how one chooses to interpret that Putin said. I interpret it as him saying solar panels are more expensive than alternatives, perhaps for the next 20-30 years. That depends on a few assumptions. A 2018 study on the feasibility of solar power (which is generally assumed is going to be largely decentralized in Africa) found ...


5

"In 2015, the United States consumed a total of 7.08 billion barrels of petroleum products" https://www.eia.gov/tools/faqs/faq.cfm?id=33&t=6 One US oil barrel is 159 litres. One acre or rapeseed gives 600 litres oil ( https://spa.merinfo.se/question/hur-manga-liter-olja-far-man-pa-ett-hektar-raps ) (I assume hemp is in the same ballpark). That gives 3....


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