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Britain has gone two months without burning coal to generate power

bbc.com

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Re: Britain has gone two months without burning coal to generate power

#91

Post by neilwilson »

TheOtherHobbes wrote: post #69
VBprogrammer wrote: post #54

Earlier quoted context omitted.

Some back of the envelope maths, he said it takes an area 18 miles by 18 miles every year to produce 7% of the UKs electricity demand. Pine trees are harvested around 30 years old (ignoring thinnings deliberately here). So to set up a 30 year rotation of 300 square miles you are looking at an area roughly the size of Wales. That seems pretty unsustainable from a UK point of view but obviously there are less densely p…

The UK already has around 12,000 sq miles of forest, which is about 13% of the area. Half of the UK's land is owned by 1% of the population - a mix of aristocrats, wealthy individuals, and corporations. There is no practical issue with mass reforestation contributing to energy self-sufficiency, but there would be huge political issues.

We need the land for people not trees. The UK has a food deficit. Nut trees would be better than pine.

Offshore wind and storage is the way forward. We need to press on with getting that sorted and save the land for other uses.

Re: Britain has gone two months without burning coal to generate power

#92

Post by twic »

VBprogrammer wrote: post #54
leonardaustin wrote: post #5

Hummm, not sure wood pellets are carbon neutral. I think the UK has just offshored its CO2 emissions to the US. Great video below explaining in more detail. https://youtu.be/6RP-jYDgiMg?t=100

Some back of the envelope maths, he said it takes an area 18 miles by 18 miles every year to produce 7% of the UKs electricity demand. Pine trees are harvested around 30 years old (ignoring thinnings deliberately here). So to set up a 30 year rotation of 300 square miles you are looking at an area roughly the size of Wales. That seems pretty unsustainable from a UK point of view but obviously there are less densely p…

> So to set up a 30 year rotation of 300 square miles you are looking at an area roughly the size of Wales.

Well, what are they using Wales for at the moment?

Re: Britain has gone two months without burning coal to generate power

#93

Post by totalZero »

torpfactory wrote: post #60
leonardaustin wrote: post #5

Hummm, not sure wood pellets are carbon neutral. I think the UK has just offshored its CO2 emissions to the US. Great video below explaining in more detail. https://youtu.be/6RP-jYDgiMg?t=100

Wood pellet burning is a temporary distraction and distortion caused by regulation that allows it to be counted as "renewable". I believe you can make a reasonable argument wood burning is carbon neutral. Unfortunately, land used for growing forests of fuel represents a terrible opportunity cost - you could grow food or let the forests absorb atmospheric carbon, provide animal habitat, re-wilding, etc. However, there…

I'm not sure you can make a reasonable argument that burning wood is carbon neutral, unless you want to open the door to saying that any CO2 emission is carbon neutral because the carbon can be reclaimed when it is converted into plant matter. It is kind of an absurd argument, unfalsifiable because it also applies to kerogen-based fuels like petroleum and natural gas, both of which begin their long life cycles as organic matter.

Burning wood to generate energy puts more CO2 into the atmosphere than burning fossil fuels to create the same amount of energy, because wood has a lower energy density. Under ideal conditions, most of that CO2 can eventually be reclaimed, if the forest is allowed to regrow. That takes decades, however, during which atmospheric CO2 is higher than it would be otherwise. This creates harms from climate change, including some that are irreversible, like ice-sheet melt and permafrost thaw. But emissions from burning wood are only partially reclaimed by forest regrowth, because:

- harvesting trees results in release of CO2 from soils, which continues for decades;

- burning natural hardwood forest and replacing with fast-growing forest plantations (a common practice), permanently elevates atmospheric CO2 because plantations don’t store as much carbon as natural forests;

- cutting and processing wood uses energy, which generally results in CO2 emissions.

https://whrc.org/burning-wood-for-energy-is-not-carbon-neutr...

Re: Britain has gone two months without burning coal to generate power

#94

Post by neilwilson »

VBprogrammer wrote: post #44
iguy wrote: post #30

This is a good discussion of the accounting of biofuels, with a guy called Tim Searchinger (there is a transcript if you don't want to listen): https://infoproc.blogspot.com/2019/11/manifold-podcast-23-ti... One takeaway is that you should think of farming trees as fuel as a competitor for land use. If it displaces growing food crops, then they will be grown elsewhere, possibly in newly cleared rainforest. Even if no…

That doesn't pass a smell test to me. Land which is used for forestry is usually not suitable for growing crops. Usually because it's on too great a slope and on poor quality soils.

Nut trees can grow there. And so can sheep and goats. Quite a lot of pine is grown in areas that would support broad lead if you gave it time.

Re: Britain has gone two months without burning coal to generate power

#95

Post by VBprogrammer »

twic wrote: post #92
VBprogrammer wrote: post #54

Earlier quoted context omitted.

Some back of the envelope maths, he said it takes an area 18 miles by 18 miles every year to produce 7% of the UKs electricity demand. Pine trees are harvested around 30 years old (ignoring thinnings deliberately here). So to set up a 30 year rotation of 300 square miles you are looking at an area roughly the size of Wales. That seems pretty unsustainable from a UK point of view but obviously there are less densely p…

> So to set up a 30 year rotation of 300 square miles you are looking at an area roughly the size of Wales. Well, what are they using Wales for at the moment?

Mostly raising talented singers and sheep.

Re: Britain has gone two months without burning coal to generate power

#96

Post by UI_at_80x24 »

skybrian wrote: post #51
hn23 wrote: post #40

Earlier quoted context omitted.

The reason wood is considered neutral is, that most of the wood is used for construction and other stuff. If you burn it and happen to burn fossil fuel as well, nothing is neutral.

Growing a tree removes carbon from the air. That's carbon-negative. Cutting it down and using it in construction is still net-negative for the wood itself. (Though probably not when you take other energy usage into account.) In the very long run, the building might be torn down and the wood might rot or burn bringing things back to zero again. Growing a tree, cutting it down, and burning the wood is carbon-neutral. B…

You are right about it being carbon neutral but only from a small frame of reference.

How is the wood cut? How is the wood transported? How is the wood processed?

Every one of these steps add carbon to the cycle. Some steps are minimal, others are huge; it all depends on scope.

I've heat my home with a wood-burning stove for 20-odd years. I have my own acreage and friends/family/farmers all contribute. Cutting down a tree, bringing it home, chopping it size so it fits in the stove are VERY energy intensive operations.

Re: Britain has gone two months without burning coal to generate power

#97

Post by gpanders »

fersho311 wrote: post #11

Anyone watch the documentary planet of the humans on YouTube? After watching that, I’m no longer sure what renewable energy even means anymore, which no longer gives these accomplishments any meaning. Can someone help with my disillusionment?

The Wikipedia page[1] has some information on the scientific inaccuracies in the film.

[1]: https://en.wikipedia.org/wiki/Planet_of_the_Humans#Scientifi...

Re: Britain has gone two months without burning coal to generate power

#98

Post by gruez »

Jerry2 wrote: post #7
evolve2k wrote: post #3

> He says the plant now uses seven million tonnes of pellets sourced from commercial forests in the US a year and says Drax will phase out coal entirely by March next year. Anyone know more about using ‘compressed wooden pellets sourced from the US’? First time I’ve heard of an easy? transition option for existing coal power plants, achieved by changing the fuel burnt.

It's called "biomass" and it's a massive scam that harms the environment. Michael Moore and Jeff Gibbs released a recent documentary on it [0] that was censored by the "green" industry. As you watch the documentary, do some fact checking on your own [1]. [0] https://vimeo.com/423114384 [1] https://planetofthehumans.com/fact-check-bible/

>that was censored by the "green" industry

Can you elaborate on this? How was this done?

Re: Britain has gone two months without burning coal to generate power

#99

Post by philipkglass »

08-15 wrote: post #83
toomuchtodo wrote: post #9

Earlier quoted context omitted.

The UK's combined wind (23GW) and solar (13GW) generation capacity is at least 3x that of nuclear (9.3GW). Capacity factor aside, nuclear is not a necessary component of a future UK grid (with the caveat that it can import nuclear generated power from France over a 2GW interconnector). [1] There are ~269 renewables projects, roughly 40GW, in the planning stages that will add to that existing renewables capacity. [2]…

Capacity factor for wind is about 20%, for solar about 12.5%, for nuclear 90%. So let me restate it for you: The UK's combined annual wind (40TWh) and solar (14TWh) generation capacity is still less than 3/4 of nuclear (72TWh). Capacity factor aside, unreliability aside, seasonal variation aside, real word aside... you can argue literally anything.

Your numbers sound out of date.

See the data tables here: https://www.ofgem.gov.uk/data-portal/electricity-generation-...

In 2019 the UK generated 51.04 TWh from nuclear and 76.55 TWh from wind and solar.

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