[macspoofing]

Because those are intermittent power sources. That is, there are times when the wind isn't blowing, and sun isn't shining, and there is no battery technology (now or coming) that is capable of storing enough energy to bridge this intermittency gap. This is why solar and wind need fossil fuel back-up. Natural gas companies are some of the biggest proponents of solar and wind projects.

[gautamcgoel]

Can you elaborate on the "or coming" part of your post? What makes you think batteries won't be substantially better 20 years from now?

[stjohnswarts]

Because we've been working pretty hard on batteries pretty hard for over 200 years, it will take a 10-20X improvement over current technology and we're not really seeing anything that is exponential like that anytime soon. I mean obviously it could happen, it's just unlikely given the past 200 years of steady improvement and not step function improvements.

[nytgop77]

My heuristic for pessimism:

We use enourmous amounts of energy and we invest enourmous amounts of money in energy production. At the same time we have neglible storage and and neglible investment in storage.

some numbers:

194MWh - capacity of Hornsdale Power Reserve in Australia

161 million A$ - it's cost (https://en.m.wikipedia.org/wiki/Hornsdale_Power_Reserve)

4 700 000 MWh - Australia's daily total consumption of energy of all fuel types (https://www.energy.gov.au/data/energy-consumption)

4700000 / 194 = 24226 - number of same power reserves to store australias power for one day.

24226 * 161 millions = 3.9 trillions of A$ - money needed to build a days capacity in Australia at current price.

(for comparison, Australia GDP is near 2 trillion A$, US GDP is 27 trilion A$)