Comment by cupofpython | Hacker News Reader

Comment by cupofpython | Hacker News Reader

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>Remarkably, if you have just enough of some more round-trip efficient storage to get you through the night, the round-trip efficiency of the ammonia, hydrogen, liquified nitrogen, or what-have-you doesn't matter very much. Solar panels are so cheap, you can afford to be wasteful.

i wonder if round-trip efficiency really is all that negligible when solar panel development and shipping is no longer subsidized by fossil fuels and must also use the energy-storage tech of choice as the predominant source of energy for anything not directly hooked up to the grid. a 20% RTE efficiency has a 5x impact on required energy to do anything. Are there enough good locations for solar to cover the needs of all long-term storage needs 5x over? Do we have enough raw materials for that many panels? Seems plausible tbh but idk

In any case, isn't ammonia incredibly toxic? whats the work-around there? we assume perfect handling of it by all parties at every level of a globally large scale operation? A gasoline leak is bad enough, but an ammonia pipeline bursting? that seems like a hard sell

Cost for solar panels is still in free fall. Nothing is being subsidized at anything like the amount we pay for oil extraction: every last barrel pumped is paid out for, cash on the barrelhead, hundreds of $billions every year. You pay for a panel exactly one time, and then it delivers for years.

The point about round-trip efficiency being negligible is that you only rarely need to draw down on those easy-to-ship, easy-to-store media. All you need is, say, 2x more panels to use to top them up again. Most of the time, those extra panels are driving synthesis to sell, generating revenue.

Shipping is always cheap. In the future, we can expect the ships to burn ammonia synthesized in the tropics.

Storage costs are falling even faster than for solar panels.

Solar can be co-sited with roofs, where it extends the life of the roof; with parking lots, where it extends the life of the cars; with reservoirs and canals, where it cuts evaporation and biofouling, and also operates cooler, thus 3% more efficiently; and with pasture and farmland, where it increases yield by reducing heat stress, and cuts water demand. So, yes, there is way more room for solar panels than you will ever want.

Solar panels are usually made of silicon, which makes up 28% of the Earth's crust. The mass of solar panels needed per kW is falling even faster than their cost.

Ammonia is toxic. But we already handle literally millions of tons of it every year without incident. It is lighter than air, so if it leaks, it can't blanket a nearby town like, say (just picking at random) methyl isocyanate.

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