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Comment by i_am_proteus | Hacker News Reader

I think the implication is that it's not necessarily better than coal because burning forests is only carbon neutral on a very long time scale. Eventually the cycle of harvesting trees, burning the wood, and planting more trees is carbon-neutral (minus any carbon from logging and transportation).

But, if the process starts with logging existing forests, this releases carbon (more than coal). It would be "better" to burn coal and plant new trees than to burn wood and plant new trees. This would result in more land being forested - but that's the point.

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My rule of thumb is, if a story vaguely implies that something is worse than coal/oil/anything made by a big pocketed corporation, but they dont come out and directly state that it is, ideally with sources, but just continually insinuate, then it's not worse, and the story is corporate propaganda to make alternatives seem futile.

EU population growth rate is sub 0.2% per year, combined with increasing agricultural output and there is actually quite a bit of land available for reforestation.

As to burning forests, fast growth wood can be harvested in decades not centuries. The goal is burning for energy not high density wood for construction. Plus burning wood releases energy from both hydrogen bonds and carbon bonds which means you get more energy per lb of CO2. Managed forests are actually a very reasonable use for available land economically vs traditional farming as they don’t need anything close to the same kinds of subsides.

In terms of energy you can hit up to the equivalent of ~60,000 tons of coal per year per square mile, that adds up fast. There are definitely ways to capture more energy, but wood is cheap and scales.

> As to burning forests, fast growth wood can be harvested in decades not centuries.

Yes, but the main problem being pointed to here is the logging of old forests (they are nature preserves), this isn't about the fast industrial tree plantations of marginal ecological value.

Where can you grow 60,000 tons of coal equivalent per square mile per year? In the US, the absolute upper end for forestry biomass is more like 6000 and that's in a tiny fraction of land areas. A "good" but unexceptional location would yield closer to 400.

Biomass is nice because you can turn it into chemicals and stored fuel, but the areal power output is very low.

60,000 is kind of the extreme outlier.

Melia dubia for example is 44m3 of wood per acre above ground biomass in the right conditions. That’s 28,000m3 per year per square mile, but a few methods which aren’t currently cost effective like extracting the root ball can apparently boost it further.

> It would be "better" to burn coal and plant new trees than to burn wood and plant new trees.

From a purely CO2 perspective, trees are just stores of carbon, just like coal. I don't get how one is better to burn than the other? If anything that should come out in favor of burning trees, because wood contains more hydrogen bonds (that oxidize to H2O instead of CO2) and because newly planted trees grow much better in logged forests than they do in coal mines.

The difference is that coal contains carbon that has been locked inside the earth's surface for at least a few million years (if not longer).

Trees on the other hand contain carbon that those trees extracted from atmospheric CO2 while growing. Burning those trees merely returns CO2 to the atmosphere that was taken from it a few decades ago. If you do that in a balanced way (growing the same amount of trees that you burn at any point of time), you may create a cycle that does not affect long-term atmospheric CO2 concentration.

> I think the implication is that it's not necessarily better than coal because burning forests is only carbon neutral on a very long time scale.

I find this assertion to be very hard to believe.

Biomass is the epitome of a renewable energy source. You gather dead vegetation or chop down trees, you burn them to generate power, you plant them again and wait for it to grow. Rinse and repeat. Coal is the exact opposite. Moreover, biomass implies recovering carbon from the atmosphere, while coal implies digging it out of the ground and dumping it into the atmosphere.

Care to present any evidence or rationale that supports your claim and lends it any credibility? I suspect that what makes your claim utterly unbelievable is making the mistake of succumbing to a kind of "slippery slope" argument, where you feel the need to go a all-or-nothing route and extrapolate what it would take to scale biomass to provide the totality of Al energy needs. In reality, biomass is scaled the other way around: project how much biomass can be realistically provided by a managed forrest, and adjust the biomass plant to meet it's needs.

Renewable is a misnomer that goes back to the early environmentalist movement. In those days the concern was about running out of energy resources, not climate change. Today we’re drowning in energy, but have a surfeit of greenhouse gases in the atmosphere.

We should Chuck the “renewable” nomenclature from the discourse as fast as possible. We don’t care about renewable we care about carbon neutral. Nuclear is non-renewable but carbon neutral, which makes it far superior to wood which is renewable but carbon spewing.

> Renewable is a misnomer that goes back to the early environmentalist movement. In those days the concern was about running out of energy resources, not climate change. Today we’re drowning in energy, but have a surfeit of greenhouse gases in the atmosphere.

I'm sorry but your post reads like a non-sequitur on semantics, and I fail to see how it adds anything to the discussion. Biomass is renewable in any of the senses you discussed: in the sense of replenishing energy sources, and in the sense of not contributing to emissions as it's role in the carbon cycle is closed.

Nuclear is good. Wood is carbon-neutral. We should use both to move ASAP from gas and coal. Especially that wood is easier to use in some existing coal furnaces.

And if you think that burning wood is carbon-spewing, then thin about what happens in all those forests once the trees age - they either get logged and used for construction, afterwords they get discarded and rot or they don't get logged, collapse and rot. Either way carbon is getting back into the air as CO2.

This is true on the scale of decades, but the problem with climate change is we don't need carbon neutrality for O(50 years). We need carbon neutrality today.

Yes maybe those forests would eventually release carbon in 2050 is all well and good, but very likely we'll have total clean tech solutions by then anyway. In contrast we only have a short window to reduce atmospheric carbon substantially to prevent significant warming by the end of the century. To the extent possible if we can keep carbon sequestered today and pay by having it released in 30 years that's a very good deal. Because it stops the runaway warming today, and it gives us three decades of investment to start sequestering atmospheric carbon.

But now a lot of infrastructure runs on coal. You can use wood instead and have this carbon captured and reused in the next 10 years or you can still burn coal while awaiting a perfect solution.

We have surplus of farmland due to farm efficiency. We have more forests in EU now than we had 10 years ago. Switching to biomass is a good step because every ton of wood that emits CO2 that will be recycled is better than 0.6-0.8 ton coal that gets burned now and adds carbon.

Nuclear fission actually is somewhat renewable in the sense that you can recycle most spent fuel through a breeder reactor and reuse it.

That is logic that works at a local and individual level but breaks down at a global and economic level.

Think of it like fish stocks. A small pond can be managed by an individual to make sure that stock levels are renewable. You are careful to not over-harvest. But an individual fishing boat at sea does not have the same control, because other boats are fishing the same waters. The fish are only renewable if there is collective effort to ensure that.

Oceanic fish stocks are a commons, and suffer from the tragedy of the commons you describe. The way I see it, modern day forests aren't, they have a clearly assigned owner.

But the atmosphere is!

>Care to present any evidence or rationale that supports your claim and lends it any credibility?

I am describing the text of the article these comments respond to. If you have not read the article, that would be my first recommendation.

I will now expose the flaw in your argument:

>biomass implies recovering carbon from the atmosphere

Cutting down a tree and burning it releases carbon into the atmosphere. Planting a new tree removes carbon from the atmosphere.

However, during the period between clear-cutting old-growth forest and waiting for new biomass to capture carbon out of the atmosphere, the process results in net carbon dioxide in the atmosphere. If one were to plant new forests on a hypothetical plot of currently-fallow land, wait for those trees to grow, and then harvest those trees, it would indeed be carbon neutral. But trees take time to grow.

Other forms of biomass operate on much faster time scale and don't have this particular problem.

> This would result in more land being forested

Why? This is an additional variable. You can add additional area in both cases. Why would burning coal add some land that you can plant new forests, and burning wood not?

Bear in mind that in Europe "plant new forest" means "change land use from agriculture" or "change non-forest ecosystem such as moorland to forest". There's isn't a lot of land that's just spare.

I know, that's why I disagree with premise that we can burn coal and magically find new land for forests.

It's a hypothetical to make the comparison apples-to-apples.

But also: for biomass to be carbon neutral compared to some baseline, there would need to be no net change in living biomass. While there's a net negative in living biomass, the cycle is not carbon neutral. The time scales are long enough that it makes a difference. In extremis, coal is not considered renewable or carbon-neutral even though, in s very technically-correct-is-the-worst-kind-of-correct sense, it is.

> It's a hypothetical to make the comparison apples-to-apples.

It's not apples to apples when you magically find some new land that does not exist in the other scenario.Biomass is not carbon neutral very short term, but coal never is.

There are some species that grow very fast - replenishment is not a very long term perspective: https://en.wikipedia.org/wiki/Short_rotation_coppice

> Biomass is not carbon neutral very short term (...)

Well, mankind has been outputting industrial emissions for the last, say, two centuries. It's very safe to assume that most managed forests around have been capturing anthropogenic CO2 emissions for the last century or so.

I take offense at that. Yes, you might be achieving the holy grail of storing carbon, but a collection of identical, equidistant trees with barely any other form of life between them is not a forest, it's a soul-crushing horror show.

Compare that to a strip mine and it is way smaller horror.

It can create place to live for animals, it can reduce particulates in the air. It's not a normal long-living forest that is grown for wood for 80-100+ years but it's still way better than burning coal.

It's not a forest. It's a field, the same as wheat or corn, just that the product is different.

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