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Wouldnt then our “green renewables” also not be green due to their production lifecycle as well? Plastics, batteries, fiberglass, rare earth metals, cobalt, etc
by ccffph 7y ago
Wouldnt then our “green renewables” also not be green due to their production lifecycle as well? Plastics, batteries, fiberglass, rare earth metals, cobalt, etc
- the8472 7y agoTo a small extent, yes. It's a matter of degree. Nuclear and renewables still have a much lower footprint than coal. It's just not zero. We don't know the full lifecycle costs of fusion plants, but at least the fuel part won't involve open pit mining, unlike uranium ore, so it hopefully will be better than fission.
- ThomPete 7y agoNuclear have a much lower fooprint than renewables, requires much less space, last longer, is more robust, doesn't require rare earth materials or support from ex coal (like wind and solar often end up doing) as a base component. Solar and wind is not even close to being in competition with nuclear when it comes to what is cleanest.
- bjelkeman-again 7y agoThis LCA study shows wind, large hydro and 4Gen nuclear to be in the same range. With solar pv being higher. https://www.mdpi.com/1996-1073/11/12/3452/htm https://www.mdpi.com/1996-1073/11/12/3452/htm
- nightski 7y agoStill that is only greenhouse gasses and not full environmental impact. Renewables take up a lot of space.
- Tade0 7y agoYes, but that space may well be someone's roof.
- ThomPete 7y agoNot for anything substantial plus there are plenty of solar and (all wind) that doesn't sit on someone's roof.
- TheOtherHobbes 7y agoDefine substantial. Domestic PV installations reliably produce a significant percentage of domestic consumption - even in countries like Germany and the UK, which aren't known for bright sun. Countries that do have bright sun typically skip straight to passive solar water heating systems, which can do an excellent job of eliminating water heating costs.
- adrianN 7y agoIt's not like the world is running out of space anytime soon.
- tomp 7y agoBut maybe we don’t want to pave the Earth with PV panels...
- pfdietz 7y agoThe world is bathed in 100,000 TW of sunlight. Current world primary energy consumption is 20 TW, 1/5000th of that amount. In contrast, 11% of the Earth's land area is under cultivation for crops. Add pastureland and that increases to 37%. Why the outrage over PV land use, when it will be just a pimple on agriculture's land use butt?
- fisherjeff 7y agoWell, taking PV array efficiency and land vs. sea area into account, that’s probably closer to 0.5% of Earth’s land area that would have to be covered with panels. Obviously not a huge amount relative to agricultural land but we’re still probably talking about a butt pimple around the size of California.
- pfdietz 7y agoPrimary energy use, though, is energy content of sources before they go through thermal cycles to get work. So one should also take into account the heat rejected in the latter. Nearly 80% of the energy content of gasoline, for example, goes out the tailpipe and radiator as heat. PV would deliver energy in high quality form, electrical power, not as heat. So less than 20 TW, probably much less, would be needed to be equivalent to today's energy usage (although precisely how much would depend on details.) Energy use will be increasing though, as the world gets wealthier. Still, this will also put pressure on agriculture to increase production, as demand for meat increases. Land constraints in the future will come from that, not from PV.
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- imtringued 7y agoI don't think it makes sense to assume that there is an energy technology that doesn't produce environmental harm. Nuclear power plants increase the temperature of rivers and they are pretty good fish killing machines.
- ThomPete 7y agoDoesent take entire chain into account. Also keep in mind wind and solar needs backup powers thats often coal. Nuclear is by far the grenest.
- imtringued 7y agoCoal is terrible in terms of load following. What are you even talking about? If anything, coal plants are economically unsustainable. They don't respond to short term changes in electricity prices and therefore still produce electricity even when they are losing money.
- ThomPete 7y agoYet they are used as a backup for both wind and solar because those are unreliable energy sources. That's what I am talking about. Coal isn't economically unsustainable I don't know where you have that from. Wind and solar covers less than 1% of the worlds energy needs even push forward to 2040 and it might do around 3%. It's not even close to being a serious contender for humans energy needs.
- chithanh 7y ago> wind and solar because those are unreliable energy sources They are unreliable but not unpredictable. Weather forecast provides adequate production estimates 48 hours, and precise ones 12 hours into the future (especially when averaged over large areas). Enough time to fire up standby power generation. Also while wind and solar are unreliable by themselves, they become a lot more reliable once you combine them. That is because when there is little wind, it is usually sunny, and when there is little sunshine it is usually windy. At night, when there is neither, the power consumption is low. The major problem that needs to be addressed with substantial amounts of energy storage is overcast winter days with no wind, when power consumption is high. > Coal isn't economically unsustainable I don't know where you have that from. According to a 2018 report[1] of the German Environment Agency (UBA), the economic cost (health and environment) of coal power is an additional 0,19 €/kWh over the generation cost. This makes it unsustainable compared to other energy sources and only profitable because the public bears this cost. > Wind and solar covers less than 1% of the worlds energy needs even push forward to 2040 and it might do around 3%. Someone should tell the Chinese, because they are already at 5% from wind alone. [1] https://www.umweltbundesamt.de/publikationen/coal-fired-power-generation-climate-protection https://www.umweltbundesamt.de/publikationen/coal-fired-powe...
- pfdietz 7y agoIn a decarbonized economy, burning no fossil fuels, why should PV emit any CO2? Nuclear, on the other hand, is going to still have lots of concrete, and making concrete emits CO2 even if the energy to calcine the limestone comes from non-fossil sources. Yes, one could capture and sequester the CO2 from concrete manufacture. But then one could also capture and sequester putative CO2 from PV manufacture. So if sequestration is on the table, the CO2 argument being made against PV in favor of nuclear just collapses anyway.
- ThomPete 7y agoThere will not be a decarbonized economy running on wind an and solar. It's less than 1% of the worlds energy consumption and won't be more than 3% in 2040. Nuclear doesn't us "lots of concrete" in any meaningful way especially not when you start factoring in the energy density. Wind and solar require huge areas, lots of rare earth metals and there is no plan for how to decommission plus, wind and solar are unreliable which means they still need backup from something else like coal, nuclear or oil. In other words there will be no decarbonized economy without nuclear or fusion or thorium.
- TheOtherHobbes 7y agoI have no idea where your figures come from, but they appear to be wildly inaccurate. https://www.iea.org/renewables2018/ https://www.iea.org/renewables2018/
- ThomPete 7y agoNo they are quite accurate. You are conflating electricity with energy. Energy is much more than just electricity. Furthermore, when you hear countries like Denmark and Germany talk about x amount of percentage being wind or solar you need to remember a few very very important things. 1) They are talking about what that specific country produces, not what it consumes. 2) What it consumes includes what it imports. 3) Wind and solar only produce electricity which is only part of our energy consumption 4) You also have to factor in the capacity factor which for wind and solar is between 20-40% and nuclear is more or less 100%. In other words, those high numbers only come from ignoring the entirety of energy needs. The renewable energy sector and its proponents are very disingenuous when they present their "success".