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whimsicalism a day ago

More sustainable/co2 neutral/renewable.

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Symbiote a day ago | parent [-]

Farmed trees are often promoted as being a great fuel, but they do very, very little for enhancing biodiversity.

The UK's largest CO₂ emitter is an ex-coal now-biomass powerplant: https://en.wikipedia.org/wiki/Drax_Power_Station

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AnthonyMouse a day ago | parent [-]

> Farmed trees are often promoted as being a great fuel, but they do very, very little for enhancing biodiversity.

Wind turbines and hydroelectric dams don't do much for enhancing biodiversity either, which is fine because their purpose is to generate electricity.

> The UK's largest CO₂ emitter is an ex-coal now-biomass powerplant

Only by counting burning biomass as emitting new CO2 while not counting the CO2 it removed from the air from being grown.

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sarchertech a day ago | parent [-]

That only counts if you grow the trees explicitly for power generation. Burning trees that already existed (as is the plan for the plant I mentioned) is like burning coal, which also removed CO2 from the air in the past.

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AnthonyMouse a day ago | parent [-]

Trees are part of the active carbon cycle. They grow while taking in CO2, then die and rot while releasing it again. Burning them does the same thing as the second one, which was going to happen on its own.

Coal isn't part of the active carbon cycle. It would stay locked in the ground indefinitely if you didn't dig it up.

Moreover, that plant appears to be getting biomass as compressed pellets from sawmill scrap wood and sawdust, i.e. it's the refuse from trees that were already being logged to make lumber. If they didn't burn it then it would go into a landfill to rot and release the carbon anyway.

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sarchertech a day ago | parent [-]

That’s not the plant I’m referring to plans to do. They’re planning to bring in 350-500 logging trucks per day.

Sure they will get sawmill scraps if they can, but if built this will be by far the largest biomass reactor in the country. When I did the math there’s not enough available scrap in the entire country to power this thing.

They’ve explicitly stated that they need 5.5 million tons of timber from the surround 250 miles of forest annually.

>Burning them does the same thing as the second one, which was going to happen on its own.

Over 50-100 years for short lived species. And much longer for longer lived species.

So yes better than coal but over the lifetime of anyone alive today it’s essentially the same thing, so it’s only really better than coal if you are looking 100 years into the future and if you stop doing cutting down existing trees at some point.

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AnthonyMouse a day ago | parent [-]

> When I did the math there’s not enough available scrap in the entire country to power this thing.

Which tracks since it's in England and they're getting pellets from the US, Canada and Europe.

> Over 50-100 years for short lived species. And much longer for longer lived species.

But who is logging old growth trees for biomass?

In if someone is cutting down a tree in a first world country it's generally either because the tree was grown intending to cut it down and they immediately start growing new trees there, or because it's going to be cut down regardless of what you do with the tree because they're removing it in order to make some other use of the land.

Moreover, you can always find that one asshat doing something ridiculous, but the world also generates a lot of scrap wood or cuts down a lot of trees just to clear the land. Burning them to generate electricity is never going to be large proportion of world power generation, but doing it to the extent that the trees were just going to rot anyway seems pretty hard to object to.

	▲	sarchertech a day ago \| parent [-]
		The plant that I was talking about when starting this thread plans on harvesting 5.5 million tons of timber per year. That’s not all that much unused wood scrap, so if you’re building a large biomass plant you’re going to end up harvesting timber. > In if someone is cutting down a tree in a first world country it's generally either because the tree was grown intending to cut it down and they immediately start growing new trees there, or because it's going to be cut down regardless of what you do with the tree because they're removing it in order to make some other use of the land. In Europe maybe. In the US and Canada it’s very common to harvest timber from naturally grown forests (vs managed plantations) that are being cut primarily for the timber.