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I'm always baffled by such statements. Can you explain in which way solar is not a "near-infinite source of energy"? I mean... there are without doubt technica
by hannob 7y ago
I'm always baffled by such statements.
Can you explain in which way solar is not a "near-infinite source of energy"? I mean... there are without doubt technical challenges and all that (but arguably less technical challenges than to do the same with nuclear), but there really is no relevant limit to the deployment of solar cells if you include things like large-scale installations in the desert.
- threeseed 7y agoEspecially if there are advancements in power distribution e.g. high temperature superconductors. This would be a game changer for the major continents like Europe, US, Africa where you could have power coming from hydro, thermal, solar, wind etc and being shipped to where it is needed.
- posix_me_less 7y agoLoss of power during distribution is not a problem that needs solving, power losses due to transmission in conventional grid are mere 5%. [1] https://en.wikipedia.org/wiki/Electric_power_transmission#Losses https://en.wikipedia.org/wiki/Electric_power_transmission#Lo... Considering how costly and inflexible all superconductors are, I don't see why they would help.
- chrisco255 7y agoThose losses are on a per 100 mile basis. 2-5% per 100 miles of line (not as the crow flies mind you). Superconductors would make a huge difference if they could build a room temperature superconductor.
- Already__Taken 7y agoExactly, when people mention losses saved by superconductors they don't mean to improve the current grid. It's to route power from the always sunny side of the planet.
- xorfish 7y agoHVDC is already below 3% per 1'000km. So connecting Europe to the Sahara is around 5% with current technology
- chrisco255 7y agoNo. Sorry the Mediterranean Sea separates Europe from Sahara (as well as several countries) and you can't do this practically by any means. Europe doesn't own the Sahara.
- xorfish 7y agoThe main problem with installing solar in the Sahara and transporting it to Europe is the political instability of the region. Laying cables across a sea or ocean is already routinely done.
- lostlogin 7y agoWe all manage with oil. The key has to be getting the resource without making the region worse, which hasn’t been the case with oil.
- chrisco255 7y agoThere's communication cables laid across the sea. There's no examples I know of High Voltage transmission with enough power to operate Europe. It's not only the instability of Sahara, but laying a cable across the sea for the transmission of enough energy to power Europe would require defense of the cables. A submarine could otherwise attack the grid and take Europe offline. This is unpractical on a lot of levels and hand-waving this as a reasonable solution is silly.
- xorfish 7y agoSo your point is exactly my point? The technology isn't a problem. Superconductors wouldn't solve anything. It is a political problem.
- duckymcduckface 7y agoThe 5% is quoted further in the article for overall grid waste. The per mile basis is purely there to compare why higher voltages for the Samer power lead to less waste.
- erulabs 7y agoSolar power is simply indirect nuclear power anyhow. If we can do what’s happening in the sun in a bottle - then no need to produce panels. If there is material in stars to produce solar power, then there is more potential nuclear power. I’m for both, and solar seems distributed in a way that makes me think it’s better for human society, but since stars are made of fissable materials - by definition there is more “potential energy” in fission than solar, since solar is simply a subset of fission at a distance.
- lorenzhs 7y agoStars are fusion reactors, not fission. They're mostly made of hydrogen and helium, which account for 98% of its mass: http://hyperphysics.phy-astr.gsu.edu/hbase/Tables/suncomp.html http://hyperphysics.phy-astr.gsu.edu/hbase/Tables/suncomp.ht.... You're going to have a hard time building a fission reactor running on hydrogen and helium.
- neuronic 7y agoSolar is fusion and not fission [1]. If you can't even get that right, why should anyone take these weird pro-fission arguments seriously in 2020? The solution is to keep using existing nuclear power and develop renewables for replacement. Nuclear fission plants take at the very least 10 years (!!) to go online from the day construction begins. And that leaves out years of planning and dealing with contracts. It's too expensive, dangerous and redundant in the face of emerging renewable tech which is becoming cheaper and more efficient by the month. [1] https://www.energy.gov/ne/articles/fission-and-fusion-what-difference https://www.energy.gov/ne/articles/fission-and-fusion-what-d...
- Reason077 7y ago> "Nuclear fission plants take at the very least 10 years (!!) to go online from the day construction begins." Yes, but that's what the small modular reactors being proposed by Rolls-Royce, and others, intend to solve. If successful, they would greatly reduce the construction time, risk, and cost of nuclear projects.
- roenxi 7y agoThe solar panels do have to be fabricated. That probably doesn't have the same scaling potential as nuclear given how much power/m2 nuclear can reach. Also, at a guess the energy in solar panels drop with the square of distance to the sun. It is unlikely to be a good choice for interstellar travel if 'advance[ing] as a species' heads in the more fantastic directions.
- hannob 7y ago> The solar panels do have to be fabricated. Let me tell you a mindblowing fact: It doesn't matter which energy technology you use, there's always technology involved that has to be fabricated.
- epistasis 7y agoIf we are getting to the point where W/m2 is an important win for nuclear, we are going to start to have serious problems with the rejected heat. A fundamental limitation of thermal steam engines is that they can only ever be 50% efficient, and you have to dump that waste heat in order to maintain power. Already, heat mitigation systems for some existing nuclear plants are starting to fail during heat waves as the climate warms. And these are expensive systems: at Diablo Canyon in California, it's cheaper to replace an entire, functioning reactor with renewables than it is to simply build a new cooling system. Which is all to say that nuclear won't scale tremendously well unless we 1) figure out fusion, and 2) figure out direct conversion of energy to electricity rather than using steam turbines to mechanically drive a generator. For the ultimate goal that many people have for nuclear, as a power source when not on earth, these sorts of advancements are also likely also necessary. Cooling in space is not a trivial matter.
- belorn 7y agoWhat I have heard, you do loose energy in transmitting power over large distances. There exist low loss transmission cables, but I don't know how effective that is over very great distance. There is also the question of how to redesign a distributed power grid into a centralized version where all the power comes from a single sources in desert areas. On top of that there are political challenges. I have a hard time imagine Europe in current climate being happy to rely exclusively on power from the Sahara.
- hannob 7y agoThe Sahara thing is ultimately just to illustrate that there's no real limit to solar energy (because the upper commenter claimed that nuclear is the only energy that is practically limitless). But of course in practice you'd do the easy things first - that is, build solar on every rooftop. No country is anywhere close to that. I guess in the future we'll use imported solar for hard to solve problems, e.g. turn it into hydrogen or synthetic fuels (which also makes the transmission loss problem much smaller), while our electricity needs will be served mostly by local wind and solar.
- chrisco255 7y agoThere's no solar energy in the Sahara at night. And then as people mentioned, there is energy lost in transmission through resistance in power lines. There's also the fact that not too many of the world's 8 billion people live within serviceable range of the Sahara, assuming you can get past the geopolitical instability in that region to construct and maintain such things. The solar cells would need constant cleaning from dust storms to keep them running at high efficiency. No, running solar on rooftops isn't the most practical use either. Depending on latitude, weather, cost of solar installation and battery installation, orientation and layout of roof to the sun, the problems with snow, rain, and hail, the lack of solar at night, the fact that none of this generates enough power for those times when you need it most like in the middle of winter in northern climates, etc. Solar and wind will never meet the growing needs of modern economy. Period. It's a pipe dream. They are great supplemental sources of electricity. They cannot power a first world economy.
- bra4you 7y agoMe too. But lets not forget, we are dealing with 16 years old kiddies here. But for you: https://dothemath.ucsd.edu/2011/07/galactic-scale-energy/ https://dothemath.ucsd.edu/2011/07/galactic-scale-energy/
- chrisco255 7y agoSolar depends on weather, location and battery storage. Solar cells also require massive amounts of physical area to produce the same amount of energy as a nuclear power plant. And you can't compare a "2 gigawatt" solar installation to an equivalent nuclear installation because nuclear will produce power 24/7 at peak capacity, rain or shine. A solar plant sees a huge amount of variability and only hits peak efficiency for a brief part of the day on clear days.
- aplummer 7y agoSolar power in the desert produces power 24/7 by keeping the molten sand hot overnight. It’s also always sunny
- Accujack 7y agoThat technology is far more expensive than photovoltaic panels.... for example, the solar thermal Ivanpah project is now obsolete for that exact reason. Additionally, The storage density of molten salt is far lower than the generation capacity of a reactor.
- ZeroGravitas 7y agoSolar plus battery near the equator can be sized for 24/7 power with relative ease. But no one would do that, because we don't need power at the same rate all the time. Near the equator, where most people on the planet live, our need for energy is correlated with when the sun is shining and air con is running and people are awake. This is why solar is better even at the mythical "baseload" than nuclear is.
- chrisco255 7y agoYou are hand waving the complexity, cost, feasibility and trade-offs of doing this.
- Accujack 7y ago>Near the equator, where most people on the planet live Nope. In fact, a minority of people live near the equator... for good reason: https://www.datagraver.com/case/world-population-distribution-by-latitude-and-longitude-2015 https://www.datagraver.com/case/world-population-distributio... Also, the base load most of us are talking about isn't created by people for the most part... it's created by industry, without which life on the equator or anywhere else would be rather primitive. In any case, the equator is going to become unlivable in the next few decades to the point where populations in equatorial areas will drop drastically.
- The_Double 7y agoNot every country has access to a desert to deploy large scale solar. Most of the EU, Russia for instance, and those places do not want to be dependent on other countries.
- Accujack 7y agoIt's probably also worth noting that photovoltaics have to be exposed to the sun to work... which means that they can't be protected by armor or bunkers, which means that they're terrifically vulnerable to terrorist or other attack.
- lhopki01 7y agoThe terrorist attack that is going to take out 1000s of square kilometres of solar panels? Surely they'd just attack a city if they had that amount of firepower? Or in the more likely case that they don't it's easier to attack power transmission than generation.
- Accujack 7y agoAssuming there are that many panels, it is in fact quite easy for any industrialized country to design a weapon that can destroy a square mile of panels or more with a single warhead. They're thin sheets of silicon covered in glass.
- kragen 7y agoA square mile is 2.6 square km. You are replying to someone who said it would be hard to destroy thousands of square km of panels. It would seem that your reply, that "it is…easy…to…destroy a square mile of panels or more with a single warhead", is not to the point. However, by coincidence, your position is right, for two reasons: 1. Single nuclear warheads routinely have blast radii of tens of km rather than, as you suggest, hundreds of meters. So in fact a single warhead can indeed destroy thousands of square km. 2. 1000km² of solar panels would be 1000 GWp; at a low-cost module price of €0.19/W (the average for 2019) that's €190 billion. Currently solar plants are not built that large, nor nearly so.