For solar panels I agree, there's a hard limit of how much energy per area the sun itself gives, and how much efficiency you can physically get out of that.
For batteries: biological creatures store more energy more densily, yet safely, so there's still headroom.
I think the general thinking is that cost is going to be the determining factor for PV. It it gets to be cheaper than paper, for ex, you could just put it everywhere.
But there are still lots of wins - we’re only in the low 20s for efficiency and mostly catching visible light. There’s also environmental, long life, etc ways to improve as well.
Solar is by far the cheapest form of energy by a significant margin. It is already at the point where it makes sense to put it everywhere, and have concentrated large scale generation.
For solar to win, we need to solve energy storage, or perhaps the energy distribution problem. There is no amount of solar which will give you power 24 hours in a day in a single location.
Energy storage is the best short term solution. If we can capture peak solar generation and move that energy to the peak demand period, we can have a serious discussion about moving away from coal for baseload generation. It won’t be needed during the day, and the demand periods covered by storage.
However, for solar to really win, we need to think bigger with our energy distribution networks. Think of a global scale distribution network, like an internet for electricity.
If you can send an IP packet from your computer across the world, why not energy?
With a sufficiently large interconnected global scale network of renewable generators, energy storage becomes less important. We don’t need gas pipelines, we need longitudinal and latitudinal HV distribution networks.
> If you can send an IP packet from your computer across the world, why not energy?
This has already begun in the form of the new transmission line under the North Sea between England and Norway, which will be used to store wind power from the UK in pumped hydro facilities in Norway. [1]
But sending electricity at grid transmission levels across major ocean distances may not pencil out economically.
Politics also comes into play. In the US for example, the Texas grid won't even attach to the rest of the national grid.
> For solar to win, [...] If we can capture peak solar generation and move that energy to the peak demand period, we can have a serious discussion about moving away from coal for baseload generation.
Why is it always solar vs coal? The generation mix depends on your network, but AFAIK, the world is already moving away from coal towards natural gas; and solar is often complemented by wind.
But afaik, solar panels currently convert only 20% of the energy to electricity, can you explain why this is close to the theoretically or practically possible maximum?
There's a theoretical limit of 55% for unconcentrated, 85% for concentrated sunlight. I'm not sure about the exact thermodynamical reasons for those numbers.
But claims of "1000x better" can physically never be true, unlike for batteries (e.g. antimatter, no matter how impractical, has millions times more energy density)
That a 528x improvement. If the price goes down in half again, quite possible with economies of scale, you have 1000x better in a significant measurement that counts.
For batteries: biological creatures store more energy more densily, yet safely, so there's still headroom.