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Ok I'm going to explain the bit that no one wants to accept about those "shockingly cheap" wind/solar W's. Which the cheapest I think I've seen are only about 1

Ok I'm going to explain the bit that no one wants to accept about those "shockingly cheap" wind/solar W's. Which the cheapest I think I've seen are only about 1/2 the cost of carbon based energy (which swings between NG and coal being the cheapest). Lets talk solar because its initially easier to reason about: So when you see $X per (K/W/G)watt compared to $Y per (K/W/G)watt for coal/ng/oil/nuke/etc your comparing what is basically the nameplate generational capacity of a renewable resource with the nameplate generational capacity of a reliable source. Then everyone gets happy and walks away. But really lets say that you get 12H of solar production a day (which is a bit hand wavy because it won't ever produce peak power in the morning/evening). So now on a given day your actually producing 12Wh of energy, but lets say for a moment you need 24Wh of energy evenly spread over the day. That same 1W NG plant can provide that. So to reach the 24Wh of reliable generation you need 2*SolarW But because 1/2 of it is at night what you need is 1xSolar during the day+1x solar to charge a 12Wh battery+1x battery*12 (which we are going to call a 1x battery from now on) Now what happens if the sun fails to shine 1 day every two weeks? Well now you need 1xSolar during the day+1x solar to charge for the night+1x battery+2x solar to charge the dark day+2x battery 1xSolar * 4+1xbattery * 3 And once every 3 months the sun doesn't shine for two days. 1xsolar*6+1xbattery*5 So, lets assume batteries cost 3x per 12Wh what 1W solar does and they last 1/2 as long (15 years say). Now lets say the battery cost per unit solar is 6x. So to just handle the case of two dark days in a row its: 6*x+(5*x*6)=36x the installed W price of solar. But in reality lets say you want 3 9's generational reliability (which is probably still two more than you get with that 36x above) how much redundancy do you need? The answer in many places where its possible the sun doesn't shine for a week or more at a time is further multiples of the above! Making solar by far the most expensive sources of energy, only comparable with wind, in just how bad it actually is. So, how does it work today? Well generally the wind/solar plants serve to green wash, and depending on the environment and the fuel costs of NG either make it slightly less expensive or significantly more vs the just running NG plants. The equation works out that one installs NG plants equal to the peak load, then installs just enough wind+solar to reduce to 0 NG consumption (usually for month or so in the spring) at peak renewable production. Any installed capacity beyond that just drives up the price. Put another way, the "battery" today is a natural gas combined cycle generator, and you can only install enough renewables until the constant operational costs stop reducing the fuel costs of the NG plant. Beyond that the prices shoot up. Now the really bad news, energy utilization has been steadily increasing, and the carbon savings have generally been going down per W generated, but the total carbon production has been holding steady or going up. In other words 0 progress over the past three decades in reducing carbon footprint. And there is literally nothing changing over the next ten+ years. We might get another order of magnitude or two of battery production but it won't make a dent. That might be enough to electrify the personal vehicle fleet, which is ~15% of carbon emissions, it won't do anything for all the new NG plants required to back up the extra electricity generation requirements for those vehicles. In ten years though, if we started today we could shutdown every coal plant and replace it with nukes while still increasing overall generational capacity to meet the demand created by the electric cars. And at least in the US we wouldn't have to open another mine, if we just took the existing waste and reprocessed it. And if we passed some national laws stopping some of the NIMBYism we could probably build them cheap enough to make the energy price competitive with carbon sources. We can play around with the install vs operational cost model, but that is sorta the summary. So, when I hear people talking about "renewables" (ignoring hydro) I hear people who don't understand energy markets, politics and engineering because even if you manage to get the market+engineering in place to support a lot of wind+solar consumption people are going to be in the streets burning down your house when they get the bill. So, yah, there is really only one replacement for a coal plan, and its a nuke plant, and it can in theory be cheaper (Nuke plants were cheaper than NG in the past) but until the NIMBY's get out of the way its going to cost more, how much more to save the planet is a political question, but even today it should be fairly easy to do without doubling the generational price.

VintageCool 4y ago
Yes, a 100% solar grid would be very expensive. But a 90% renewable grid backed by 10% natural gas would be pretty cheap. And it's already rapidly under construction right now, and the natural gas infrastructure for it already exists. It would get us 90% of the carbon benefits, and buy time to figure out how to clean up the last 10% of the grid. 90% nuclear plus 10% hydro would be a fine end state. But we're at a standing start. The incremental change from "we're building 1 nuclear power plant which is years behind schedule and wildly over budget" to "we're simultaneously building 50 new nuclear reactors" is immense and I do not see how we get past it.
- StillBored 4y ago
  Except that its nearly impossible to get to 90% with either wind or solar by itself because when you look at the weather data the average capacity factors are really misleading. If you look at the data and say, I'm at 40% what does it take to get to 60% its many multiples overbuild. Mixing them helps a bit, but is nowhere near a solution either. The problem boils down to the fact that you can't overbuild enough to solve the problem of the wind not blowing or the sun not shining for days at end. Which sounds uncommon but that is what happens. The wind goes gangbusters for months on end then sits there doing nothing for a week or two and your producing at <10% of the rated capacity. Sometimes you can replace it with solar, sometimes not if you have two random sequences with probabilities that they produce nothing for a while, eventually they overlap and you are SOL. Someone should really build a proper weather + price simulation that shows what having 8x idle windmills and a couple overbuilt solar farms and idle gas-plant (which all need maintenance and their bonds paid) for 70% of the time does to the price of electricity. Because that is what happens to get to 90% when your not selling the excess/buying it back from C02 sources and then confusing people with gross consumption vs net. Maybe someone can dump all that excess power into CO2 recapture or something, but at the moment the economics are crazy bad. And I might buy that every bit helps, but we are in many cases going backwards, doing the same thing we did for the past 10 years for the next 10 is going to be even more disastrous as its been from 2010-2020. The carbon output needs to go to 0, not 90% of what we did last year. The richer countries should all absolutely be economy wide carbon neutral, and that isn't going to happen because no one has airplanes or new electric rail, or electric plant build plans to get the 2x electric demand increase required to start actually reducing transportation and heating Co2 much less actually have a grid that only sources 10% of its energy from carbon which isn't already there via Nukes or Hydro. And I love the downvoters who are having their feeling hurt because they don't want to believe that renewables and batteries wont solve this problem anytime soon. So the short version is, that until you understand that a solar farm at 40% or a wind farm with an average 30% capacity factor can't produce 100% of the required generation when you 3x overbuild them, you won't understand why solar+wind doesn't work.

VintageCool 4y ago

Yes, a 100% solar grid would be very expensive. But a 90% renewable grid backed by 10% natural gas would be pretty cheap. And it's already rapidly under construction right now, and the natural gas infrastructure for it already exists. It would get us 90% of the carbon benefits, and buy time to figure out how to clean up the last 10% of the grid. 90% nuclear plus 10% hydro would be a fine end state. But we're at a standing start. The incremental change from "we're building 1 nuclear power plant which is years behind schedule and wildly over budget" to "we're simultaneously building 50 new nuclear reactors" is immense and I do not see how we get past it.

StillBored 4y ago
Except that its nearly impossible to get to 90% with either wind or solar by itself because when you look at the weather data the average capacity factors are really misleading. If you look at the data and say, I'm at 40% what does it take to get to 60% its many multiples overbuild. Mixing them helps a bit, but is nowhere near a solution either. The problem boils down to the fact that you can't overbuild enough to solve the problem of the wind not blowing or the sun not shining for days at end. Which sounds uncommon but that is what happens. The wind goes gangbusters for months on end then sits there doing nothing for a week or two and your producing at <10% of the rated capacity. Sometimes you can replace it with solar, sometimes not if you have two random sequences with probabilities that they produce nothing for a while, eventually they overlap and you are SOL. Someone should really build a proper weather + price simulation that shows what having 8x idle windmills and a couple overbuilt solar farms and idle gas-plant (which all need maintenance and their bonds paid) for 70% of the time does to the price of electricity. Because that is what happens to get to 90% when your not selling the excess/buying it back from C02 sources and then confusing people with gross consumption vs net. Maybe someone can dump all that excess power into CO2 recapture or something, but at the moment the economics are crazy bad. And I might buy that every bit helps, but we are in many cases going backwards, doing the same thing we did for the past 10 years for the next 10 is going to be even more disastrous as its been from 2010-2020. The carbon output needs to go to 0, not 90% of what we did last year. The richer countries should all absolutely be economy wide carbon neutral, and that isn't going to happen because no one has airplanes or new electric rail, or electric plant build plans to get the 2x electric demand increase required to start actually reducing transportation and heating Co2 much less actually have a grid that only sources 10% of its energy from carbon which isn't already there via Nukes or Hydro. And I love the downvoters who are having their feeling hurt because they don't want to believe that renewables and batteries wont solve this problem anytime soon. So the short version is, that until you understand that a solar farm at 40% or a wind farm with an average 30% capacity factor can't produce 100% of the required generation when you 3x overbuild them, you won't understand why solar+wind doesn't work.