[jaggederest]

> and will never be.

Why do you think that? Absent some other primary power source like fusion, solar energy is the upstream producer of all the energy we currently use. Using it directly seems like the most obvious answer, especially when replacing e.g. all the earth's energy usage would only take, say, the size of Arizona

[lukan]

To quote Wikipedia for further context:

"The total solar energy absorbed by Earth's atmosphere, oceans and land masses is approximately 122 PW·year = 3,850,000 exajoules (EJ) per year. In 2002 (2019), this was more energy in one hour (one hour and 25 minutes) than the world used in one year."

[vlovich123]

Saying solar is the upstream of fossil fuels is a technicality. Fossil fuels are more like a battery that’s stored millions of years of solar energy (+ the earth itself contributed a lot of energy). Solar cells are more like plants and cannot be used to replace batteries and our current battery tech can’t improve fast enough to supplant fossil fuels in the time frames needed.

Interesting that you mention fusion though considering fission is available today and provides a substantial amount of power (not to mention actually reduces the amount of fossil fuels whereas solar has a negligible impact on fossil fuels and at best is only absorbing energy growth).

[ben_w]

> our current battery tech can’t improve fast enough to supplant fossil fuels in the time frames needed.

I disagree. The tech itself already good enough to supplant the majority of cases, which in turn gives us more time for the things that remain (such as long-haul aircraft).

That said, I may be a little on the optimistic side about how much warming the ecosphere can take. If it's already too hot, then yes, naturally you are correct.

> Interesting that you mention fusion though considering fission is available today and provides a substantial amount of power (not to mention actually reduces the amount of fossil fuels whereas solar has a negligible impact on fossil fuels and at best is only absorbing energy growth).

That's not what the graphs show: https://ourworldindata.org/electricity-mix

• Coal: down since 2012

• Gas: close enough to steady since 2012

• Nuclear: down since early 2000s

• Wind and solar: up

Looks to me like gas mostly replaced oil (since the late 90s); and that wind+solar is displacing nuclear (since the former became big enough to show up on a graph).

[pyrale]

> That's not what the graphs show

The graphs you provided show that coal and usage are still growing in absolute numbers. They're only going down in perentages. So, aside from oil (which is mostly still there), nothing was displaced.

The only significant thing we learn is that we've doubled our electricity usage since 2000. The share of low carbon electricity generation barely moved since 1985. Renewables just helped avoid it crumble due to hydro not being scalable.

[XorNot]

If batteries were literally free today, they still wouldn't be good enough due to the cost in support electronics required to put them on the grid (which is currently about price parity with batteries per watt).

EDIT: and those electronics also degrade - a lifespan of 20 years would be reasonable at scale.

[svnt]

So you’re charging twice for the grid tie? Because the reason for installing batteries would be 1) to not grid-tie, or 2) to grid-tie along with a renewable energy source, which if it is a commercial site, is already grid-tied.

[XorNot]

It's the same thing: the inverters and support electronics needed for batteries currently cost, per watt, about the same as LiFePO4.

You can't run "bare" LiFePO4: you're either forming a grid, or you're connecting to one. Both involve BMSes and inverters.

[jaggederest]

But that's already cheaper than building new coal or natural gas plants. The cost per watt of solar plus battery, right now, is the cheapest available form of power. I don't understand why you don't think that it's going to replace a majority of primary and secondary energy usage on the planet relatively quickly.

I'd bet a dollar that, in 50 years time, nearly all energy usage is going to be primitive biofuels or solar-PV-origin.

[svnt]

That’s a cost on a renewables installation though, it doesn’t need to be loaded on the batteries. You aren’t installing bare solar panels either.