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Comment by thatfrenchguy | Hacker News Reader

Yup and when there's no sun and no wind, like in winter in most places, you need something else, or batteries, which are ridiculously expensive both in $ and CO2 per kwh. Solar and Wind just can't do base load today, and you can't turn off the natural gas / coal plants that back them when they don't work.

This is a classic case of "doing the first 50% is easy, doing the last 50% is 99% of the work".

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Renewable energies are much more diverse than just solar and wind. There is also waterpower and biomass which makes a considerable part of renewable energy in many countries.[1] Niche sources like geothermal and tidal power might become more important in the future. There are other types of energy storage available and in research than batteries.

Then there is the path to improve energy efficience in industry and private consumption, which both have a lot of potential, and to replace fossil energy sources outside of electricity production with renewables, such as heat-pumps for buildings.

[1] E.g. for Germany, biomass is almost as important as solar for electrical energy. Source: https://www.destatis.de/DE/Themen/Branchen-Unternehmen/Energ...

Um, isn't biomass just burning wood and waste? How is that helpful? It seems to be pretty regressive.

https://energytransition.org/2020/07/the-secret-burning-of-t...

Burning wood/biomass or gas generated from biomass releases the CO2 that has been captured by the plant while growing. Replanting the same plant will capture the same amount again. It’s effectively solar energy using photosynthesis instead of solar cells. So it’s a renewable energy, as long as you replant what you harvest.

The problem correctly pointed out in the article is that often the replanting comes after the harvest, or does not effectively happen at all - at least for wood pellets.

Isn't that an inaccurate simplification? A lot of harvested wood is not from tree plantations but from old(ish) growth forests. It also takes decades to regrow trees so the carbon capture is taking place over an extremely long time compared to the near instant release from burning the wood. Add to that the emissions from harvesting the trees using heavy equipment, transporting them, and processing them into pellets. Burning wood is also pretty inefficient when it comes to energy or heat production and it releases a lot of particulate matter. Of all the renewable options it's obviously the worst.

I would imagine it taking out plenty of minerals and nutrients from the soil though, needing constant fertilizer usage which comes with its own set of problems.

The minerals remain in the ashes. Other nutrients may be an issue, but for example when producing biogas, they’re essentially in the leftover parts of the plant. Biogas is mostly methane, so carbon and hydrogen.

Oh I see, thanks!

There is promising process to burn biomass a low oxygen environments producing biochar(black carbon residue) without releasing CO2. This process is still in testing stages and is not deployed at scale with unclear scaling and costs.

https://www.american.edu/sis/centers/carbon-removal/fact-she...

Pretty sure you can turn natural gas on and off to some degree to back the solar, that's part of why everyone likes it so much.

Turning on a power plant is a slow and cumbersome process. If you need them to handle loads in excess of renewable capacity, or to handle sudden lows, you unfortunately need to keep them running...

What about this? https://www.ge.com/power/transform/article.transform.article...

Seems like some types can start in five minutes.

Uh, winter is windier than summer, caused by the stronger temperature gradients.

In the last 12 months in Denmark, wind produced over 3 times more power in January and February (the coldest month of the year) than it did in August. This is completely opposite of solar which peaks in July. In that sense they complement each other quite well.

Reference: https://ens.dk/service/statistik-data-noegletal-og-kort/maan...

What an antiquated argument. If you can't understand Geoffrey Moore's crossing the chasm and what those trends look like in market segments, I can't help you

https://en.m.wikipedia.org/wiki/Energy_in_California#/media/...

I don't need a degree from HBS to see where this is going

There's plenty of wind across the world in winter.

Why wouldn't there be sun in the winter in most places?

In the northern hemisphere the winter solstice is five days from today.

Where I am, in Seattle, the sun will be above the horizon for only about 8.5 hours. It will also likely be cloudy.

Contrast this with the summer solstice, where we get about 16 hours with the sun above the horizon.

Less sun, more wind, vs no wind and no sun.

I don't know what GP meant about "most places", but I guess generally places that have a winter (away from the tropics, that is) are cloudier in the winter, as well as by definition having lower solar irradiation. Most of Europe is in the unenviable position of having higher power requirements precisely when solar potential is at the lowest[0].

[0]: https://www.researchgate.net/figure/Typical-winter-and-summe...

The power requirements are fixable by better insulated housing (see eg passive houses).

Practically free natural gas has kept people from investing in energy efficient housing, just like in warmer places where people use AC wastefully in poorly insulated buildings.

Ironically during a nuclear winter event which may or may not be a fraudulent science meme concocted during the cold war. And yet we have had points in fairly recent human history where we had years long stretches of problems caused by volcanic activity. All we need then is some way to turn nuclear fuel directly to enriched calories.

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