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by elsonrodriguez 3244 days ago
Has there been consensus on whether renewables can power our society and industry on their own? Or for that matter generate more power than we currently need to drive further progress?
2 comments

If you consider only electrical power generation, in some areas, yes renewable are competitive for some hours of the day.

As a fraction of our total energy consumption, they barely register.

It only takes a few hours of sunlight to power humanity for a year. The amount of energy is not the question, it's scaling up collection.
For a while the amount of energy is certainly a question. If it takes 100 gigawatts to produce a solar panel, but that panel only returns 75 gigawatts over its usable lifespan (including maintenance), then that's not a good look.

Even if solar generated 1.25 watts per watt to contruct/transport/install/maintain, it still isn't enough.

Now if solar is at the point where it was generate 5 watts per 1 watt, we're in business.

Google "solar pv eroei". We are past the point of positive energy return.
Wikipedia says: 80.0 for Coal

100.0 for Hydro

75 for Nuclear

18.0 for Wind

6.8 for PV Solar

I saw lower estimates for PV solar elsewhere hovering around 1.0 though, apparently the methods are controversial.

Either way, 6.8 is a still science experiment territory compared to other methods.

Come on, knock out being disingenuous. Science experiment territory? California and Germany have so much solar generation, they're having to take active measures to deal with the supply. And solar PV manufacturing capacity is only growing each year.

The U.K. Is closing the last of its coal plants in less than 5 years: https://www.theguardian.com/business/2017/jul/19/how-coal-lo...

That article shows a graph indicating that Gas is taking over for the lack of coal plants, and wind/solar are plateaued.

People want a high return on their energy investment to power modern society.

I'm sure solar will get better, and I encourage the fledgling consumer market and small-scale deployments to improve the tech, but it's not ready today, and the longer idealists keep peddling the idea that it IS ready, the longer we accelerate global warming.