Comment by aksss | Hacker News Reader

Comment by aksss | Hacker News Reader

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You can't make an argument that it's carbon neutral -- They don't just burn deadfall, and you can't grow trees faster than you can burn them.

Prior to coal, the developed world burned massive amounts of wood, which contributed to massive deforestation. This is literally a step backwards, and not in any good way. When civilization burned wood for energy >500 years ago, sure, because demand was so low. But by the 1700-1800's demand for energy was so high that burning wood was untenable - coal literally saved the forests. Today, energy demands are exponentially higher, and there's no chance biomass is going to be better than coal from an impact standpoint.

I hate to disagree on renewables, but I think there is also no way renewables as we think of them today (wind, solar, batteries) are going to be the answer either. At best they are a tool enabling independence from grids, but from a worldwide energy demand perspective, they are untenable. I think Michael Moore's recent film did a decent job of outlining the problem. Next gen nuclear is probably our only hope save population reduction (hello COVID).

> you can't grow trees faster than you can burn them.

This is probably true for the UK (large population, not a lot of forest or areas to plant forest).

For e.g. Canada or Sweden it would seem possible. Sweden has 25k square meters (2.5 hectares, or 5 football fields) forest peer person. 85M cubic meters per year is cut down which is around 2% and roughly the same area planted (8.5cubic meters per person). The energy content of it is 150-200Twh which is comparable to Sweden’s energy consumption of 350Twh/year.

Obviously as little as possible is really used for energy because the value in wood for other products (timber, paper) is higher, but at least it shows that the forest as a source of energy is viable and largely sustainable. All that’s needed is a huge country full of mostly forest. Places that don’t have ten thousand trees per head to begin with can’t do this obviously, and countries that do have trees will much rather sell toilet paper and bookshelves to the UK than burn pellets.

Mass reforestation is possible in a generation or two though... In Lithuania for example a lot of reforestation was done in the later half of the last century, the percentage of the land that is forested now is 33% compared to 20% in the 40s.

http://www.china-ceecforestry.org/wp-content/uploads/2017/01...

That Michael Moore film is pretty terrible and doesn't contain the best available and most recent science. I wouldn't consider it a reliable source.

I explained in another comment that Michael Moore isn't the first, nor most reputable, to make these points. He's the first to expose the casual consumer to the problem set.

Suggested reading: https://www.gatesnotes.com/Books/A-Rational-Look-at-Energy-E...

"pretty terrible" and "best available and most recent science" are squirrelly evaluations. To be specific, you're alluding to the idea that the most recent technology improves the efficiency of solar panels and may extend their lifespan, but these marginal improvements in efficiency and lifespan aren't enough to cast aside the incredible costs in strip mining (ecosystem destruction and fossil fuel energy use), manufacturing (energy use), transportation (energy use), installation(energy use and further processed materials), and operations/maintenance (energy use, e-waste). I mean, that's a quantifiable cost to balance against quantifiable (and intermittent) output and the numbers don't bode well for renewables scaling up/out and truly denting fossil fuel consumption.

The core problem is worldwide energy demand is climbing higher and faster than renewables will ever be able to address. For the fractional role they play, the payout of renewables is undercut by the fact that fossil fuels are used to produce and emplace renewable infrastructure, renewable infrastructure (at a facility level) has an enormous environmental footprint (read: habitat destruction), and has to be replaced in a few decades at best. They are producing energy maybe 50% of that time, and despite the improvements in storage tech (which has its own environmental issues), you still need to back up the renewables facilities with.. fossil fuels.

All this is to say that we need to be looking at other sources (e.g. safe nuclear) to displace fossil fuel.

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