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One complication is that burning fuel is so much less efficient than electrical usage If you ignore that, then it radically changes the impression you get from

One complication is that burning fuel is so much less efficient than electrical usage If you ignore that, then it radically changes the impression you get from these stats. The technical terms are "primary energy" (the amount of energy you put in as fuel) and "final energy" the actual useful stuff you want done. Cars moving to EV will reduce the need for "primary energy" by about 4x if the useful final energy remains flat. Similar for heat pumps for home heating.

ThomPete 4y ago
The problem with that argument is that wind and solar needs backup from fossil fuel.
- dmbche 4y ago
  Or a buffer system with batteries - there are a few options that are being researched!
- ericd 4y ago
  There’s always wood… those stoves have gotten surprisingly efficient, and no new carbon in the carbon cycle, it’s basically a solar battery.
  - doublesocket 4y ago
    Except they produce horrendous small particle pollution, which even the most efficient stoves haven't solved. https://amp.theguardian.com/environment/2023/feb/14/wood-burning-air-pollution-uk-doubled-decade https://amp.theguardian.com/environment/2023/feb/14/wood-bur...
    - Pxtl 4y ago
      I am curious if wood-burning technology would be a suitable solution for rural settings where lower population density means particulates and smog are a lesser concern. Pellet stoves for heating, wood-gas for long-ranged vehicles. But while trees are a renewable fuel, they still mean converting carbon from a sequestered place (a tree) into being released into the air.
      - brianwawok 4y ago
        Trees are net neutral. Tree starts as a seed. Grows up and sequesters X tons of carbon. Tree is burned, releases X tons of carbon. Tree is re-planted, grows up, sequesters X tons of carbon. Tree is burned, releases X tons of carbon. If everything in the world right now was wood powered, we would not have a global warming problem. We would have massive tree farms sequestering the same amount of carbon we are releasing. (We might have a soot and particle problem, but that's another story). The problem with oil and coal, is we have no way to make more. We burn oil and release carbon.. how are we making more oil and pumping back underground to sequester that carbon?
        throwbadubadu 4y ago
        Very true, but we likely couldn't have that amount of farmland for what we currently just pull out of earth with millions of years of sequestring.. not sure if getting rid of most of the livestock needs would free enough ("Livestock takes up nearly 80% of global agricultural land, yet produces less than 20% of the world's supply of calories").. are there any calculations how many tree farms we'd need besides a huge solar/wind/geothermal mix?
        brianwawok 4y ago
        I don't know the math to globally power the world with wood. I don't think it's even a good idea. But I don't feel bad when I burn firewood pulled from a local forest. As that burning is not adding carbon to the world overall.
        TravelPiglet 4y ago
        Discounting all the power consumed planting, growing, cutting down and delivery of the logs to the power generator.
        7952 4y ago
        We don't have a way to make trees quickly enough. In the timespans relevant to climate change it is far from neutral.
    - ericd 4y ago
      Looking at the report that that was based on (page xiv on https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1124738/chief-medical-officers-annual-report-air-pollution-dec-2022.pdf https://assets.publishing.service.gov.uk/government/uploads/... ), it looks like the efficient stoves are at about 1/15-1/10 the open fire amount. Those “450x” numbers are compared to methane, which is close to zero particulate, so it’s a little misleading. But burning methane means you’re adding prehistoric carbon to the atmosphere. I’m guessing that if all the open fires were instead “low particulate” stoves, then it wouldn’t be a concern compared to PM2.5 generation from vehicles. I don’t see a perfect here until we all have heat pumps driven by nuclear.
      - ericd 4y ago
        This is kind of interesting: https://www.bts.gov/content/estimated-national-average-vehicle-emissions-rates-vehicle-vehicle-type-using-gasoline-and https://www.bts.gov/content/estimated-national-average-vehic... Exhaust particulate per mile has plummeted over the past couple of decades! By comparison, EPA stoves put out a couple grams of particulate per hour. But, it seems like it's not apples to apples, because brake dust is metal dust, whereas wood smoke tends to be mostly organic compounds. Maybe the body is better at dealing with organic wood smoke compounds? We've certainly been heavily exposed over many generations. Also, seems like there are some efforts to make electrostatic filters for fine particulate in flue gas: https://enervex.com/systems/particle-filter-system-for-stoves-and-fireplaces https://enervex.com/systems/particle-filter-system-for-stove...
- ljf 4y ago
  Wind and solar need back up yes - but it doesn't have to be from fossil fuel. Currently that is often the cheapest and quickest - but batteries and other energy storage are fast becoming economical. We are already using less non-renewables each year.
  - deleted 4y ago
    [deleted]
  - vixen99 4y ago
    Fast becoming economical? How fast? Current cost for battery storage I've seen quoted (open to correction) is around $600K per MWh. For every MW of wind or solar power that would be $120 million. Wind farms at around $1.5 million per MW ie., around 80 times that. And are there that numbers of batteries available? Currently dependent on availability of cobalt, lithium,manganese and nickel with China as the main supplier of these and world’s largest producer of graphite, the primary anode material for Li-ion batteries.
    - SuoDuanDao 4y ago
      Batteries are currently following their own version of Moore's law, though they double in quality (or halve in price) every 48 instead of every 18 months. Of course, that isn't a trend that can continue forever, but it doesn't need too many more iterations to be the only game in town.
    - bryanlarsen 4y ago
      8minute energy is building solar plants with overnight battery backup for 4 cents/kWh. https://www.businesswire.com/news/home/20200423005264/en/8minute-Solar-Energy-Expands-Development-Pipeline-to-18-Gigawatts-with-New-Solar-Plus-Storage-Power-Plants https://www.businesswire.com/news/home/20200423005264/en/8mi...
    - seanmcdirmid 4y ago
      Batteries are much cheaper today than they were yesterday, and it’s a clear push downward over time. China being the “main supplier” has more to do with them undercutting everyone else in refining by not paying attention enough to their environment, it isn’t sustainable. All of these raw materials have ample reserves outside of China. Some of battery economy comes from that, but not most of it. There are other ways to store energy than batteries. The Pacific Northwest and even California has a lot of pumped storage hydro capacity. Hydro is a renewable that can be used on demand, and can be combined with other renewables to move water back up to reservoirs.
- ZeroGravitas 4y ago
  It's not really a problem, even just moving all fossil fuels from heating and transport and using it in electrical generation gets you a 4x gain, from which you lose about 50-60% when turning it to electricity, so still ahead by about 2x even before you start adding in the wind and solar. Plus we already built all that storage for gas and oil, might as well use it as part of the transition.
  - FinnKuhn 4y ago
    Additionally with an ever improving grid in Europe local variables such as weather or seasons be can also partially balanced.
    - ZeroGravitas 4y ago
      Yeah, another story covering this had interconnects as just below gas in rank order of usage. Also, despite that large import, UK was a net exporter for the first time in a while last year since France was having issues with its nuclear fleet.
      - stuaxo 4y ago
        We need to get more interconnects between Scotland and England. They are building them, but in the sea which could be interesting with an annoyed Russia. Wind farms were built at sea, on the surface because of nimbyism on land, but being ever cynical I think the real reason was to push the cost and difficulty up giving oil companies more time. Later, during Liz Truss's short and disasterous tenure, just as solar panels were getting very cheap, even very low quality farm land was reclassified as a strategic asset for food to be grown on and no solar. In what was possibly a distraction wind was now to be allowed on land (of course it's much less convenient to put up a wind turbine than to get some very cheap solar panels and that's before all the nimby groups, some of which get dark money funding).
  - robertlagrant 4y ago
    > from which you lose about 50-60% when turning it to electricity Does this include transmission losses? I think they average 10% for UK electricity.
- Pxtl 4y ago
  With what argument? Parent post was talking about measuring energy needs and how efficiency of consumption works, not wind and solar. Did you mean to reply to a different post?
deleted 4y ago
[deleted]
contravariant 4y ago
While that's true you do need to take into account the limited efficiency of power plants as well, especially when it comes to heating. Simply burning gas to generate heat is basically 100% efficient, if you convert it to electricity first you'd need a COP of at least 1.7 to recover the energy lost while generating the electricity.
- bryanlarsen 4y ago
  A good heat pump has a COP of 4.
  - dahfizz 4y ago
    In ideal conditions. Even good heat pumps with COP >=4 will drop below 2 when it's cold out
    - throwaway473825 4y ago
      If it's very cold, yes. But the average should still be well above 3: > Similarly, in Finland, tests of air-to-air heat pump systems from various manufacturers resulted in COPs of 3 at -10C and 2 at -20C. Source: https://www.carbonbrief.org/guest-post-how-the-energy-crisis-is-boosting-heat-pumps-in-europe/ https://www.carbonbrief.org/guest-post-how-the-energy-crisis...
    - bryanlarsen 4y ago
      Judging by how much insulation the typical English house has, it doesn't get cold there.
      - stoobs 4y ago
        Not as cold as the Nordics, sure, but depending on cycles, it can drop a few degrees below freezing between November - March The main issue is that homes were designed to trap and keep heat in, rather than true insulation, which means that as summers get warmer, our homes turn into ovens, with no way to cool them down properly. Case in point last summer with UK temps hitting 40C and above for a few weeks. Government are trying to kill off the old gas boilers though, with heat pumps being pushed very heavily, not sure if they're enforcing it yet or not though. Apparently they're also looking at switching out natural gas for a hydrogen mix, but that means having to rework a lot of the piping/valves as hydrogen needs much higher standards than currently applied.
tpoacher 4y ago
Efficiency is only one aspect of the equation. Storage is another one. As is multiplicity of energy inputs. I still have no idea why nobody uses heat reservoirs for shower hot water, like they do in the Mediterranean. (it's not a sun coverage problem, because contrary to popular anecdotes, the UK actually gets quite decent sun coverage a lot of the time)
- ZeroGravitas 4y ago
  Main reason is that gas was heavily subsidised and promoted for a bit when they were pumping it from the North Sea. That was obviously short term stupidity at the time, but has only become more so with hindsight. Compare with Norway that also has North Sea gas, but heavily pushed heat pumps and is a market leader.
  - makomk 4y ago
    That's not obvious at all. At the time that the UK switched to gas, Norway was pushing resistive electrical heating and not heat pumps - and that only worked for them because nearly all of their electricity came from hydroelectric generation. The push for heat pumps is much more recent, with only a few thousand households in Norway having heat pumps as recently as 2005. The UK doesn't have the geography for that kind of large-scale hydroelectric, and there's a huge efficiency and equipment cost to using resistive electric heating rather than burning fossil fuels directly when your electricity has to be generated from fossil fuels. Also, the coal that cheap natural gas largely replaced in the UK was directly killing a bunch of people by causing pretty nasty pollution. In general, a lot of comparisons with other countries that get published in the British press are like this - they ignore important differences between the UK and those countries or problems and costs associated with what they're doing because the goal is to make it seem like there were easy options that the UK missed out on because our government is evil, not to actually help people understand the world.
    - _oyks 4y ago
      True - and fair point on the UK comparisons. Though of course, sometimes there are easy options that the UK missed out on because they are inept and apathetic, which would vindicate some of those comparisons to some extent.
slashdev 4y ago
When it comes to usage in heating, burning fuel is as efficient as it gets. All the chemical energy (available in that oxidation reaction) is converted to heat. Electricity involves more overheads in generation and transmission.
- yrro 4y ago
  Some of that heat goes up the chimney. A good quality log burner, used correctly (and I believe that most people who use log burners have no effing clue how to do so) is at best 60-80% efficient. Plus you have to account for the energy used to grow, harvest, season & transport the wood, even before you throw 20-40% of it away when you actually burn the damn stuff!
  - nindalf 4y ago
    I think GP might be referring to a gas burning boiler.
    - yrro 4y ago
      Same principle just with a different efficiency number. I doubt any but a fraction of combi boilers are 98% efficient: most people run them too hot, so they aren't able to recover sufficient energy to reach that goal. But in any case, you now have to account for installing and maintaining the gas network, refining the oil into gas, shipping the oil to the refinery, extracting the oil in the first place, exploring for the oil in the first place, and so on. It's far more efficient to burn that fuel to move existing energy from one place (outside) to another (inside)... you can turn 1J of fuel into 4J of heating if you're lucky!
- nindalf 4y ago
  Burning fuel is pretty efficient, until you realise that heat pumps have an efficiency greater than 1. So a heat pump driven by electricity uses less energy than burning fuel in a boiler. If the electricity is renewable, so much the better.
  - 4y ago

ThomPete 4y ago

The problem with that argument is that wind and solar needs backup from fossil fuel.

dmbche 4y ago
Or a buffer system with batteries - there are a few options that are being researched!
ericd 4y ago
There’s always wood… those stoves have gotten surprisingly efficient, and no new carbon in the carbon cycle, it’s basically a solar battery.
- doublesocket 4y ago
  Except they produce horrendous small particle pollution, which even the most efficient stoves haven't solved. https://amp.theguardian.com/environment/2023/feb/14/wood-burning-air-pollution-uk-doubled-decade https://amp.theguardian.com/environment/2023/feb/14/wood-bur...
  - Pxtl 4y ago
    I am curious if wood-burning technology would be a suitable solution for rural settings where lower population density means particulates and smog are a lesser concern. Pellet stoves for heating, wood-gas for long-ranged vehicles. But while trees are a renewable fuel, they still mean converting carbon from a sequestered place (a tree) into being released into the air.
    - brianwawok 4y ago
      Trees are net neutral. Tree starts as a seed. Grows up and sequesters X tons of carbon. Tree is burned, releases X tons of carbon. Tree is re-planted, grows up, sequesters X tons of carbon. Tree is burned, releases X tons of carbon. If everything in the world right now was wood powered, we would not have a global warming problem. We would have massive tree farms sequestering the same amount of carbon we are releasing. (We might have a soot and particle problem, but that's another story). The problem with oil and coal, is we have no way to make more. We burn oil and release carbon.. how are we making more oil and pumping back underground to sequester that carbon?
      - throwbadubadu 4y ago
        Very true, but we likely couldn't have that amount of farmland for what we currently just pull out of earth with millions of years of sequestring.. not sure if getting rid of most of the livestock needs would free enough ("Livestock takes up nearly 80% of global agricultural land, yet produces less than 20% of the world's supply of calories").. are there any calculations how many tree farms we'd need besides a huge solar/wind/geothermal mix?
        brianwawok 4y ago
        I don't know the math to globally power the world with wood. I don't think it's even a good idea. But I don't feel bad when I burn firewood pulled from a local forest. As that burning is not adding carbon to the world overall.
      - TravelPiglet 4y ago
        Discounting all the power consumed planting, growing, cutting down and delivery of the logs to the power generator.
      - 7952 4y ago
        We don't have a way to make trees quickly enough. In the timespans relevant to climate change it is far from neutral.
  - ericd 4y ago
    Looking at the report that that was based on (page xiv on https://assets.publishing.service.gov.uk/government/uploads/system/uploads/attachment_data/file/1124738/chief-medical-officers-annual-report-air-pollution-dec-2022.pdf https://assets.publishing.service.gov.uk/government/uploads/... ), it looks like the efficient stoves are at about 1/15-1/10 the open fire amount. Those “450x” numbers are compared to methane, which is close to zero particulate, so it’s a little misleading. But burning methane means you’re adding prehistoric carbon to the atmosphere. I’m guessing that if all the open fires were instead “low particulate” stoves, then it wouldn’t be a concern compared to PM2.5 generation from vehicles. I don’t see a perfect here until we all have heat pumps driven by nuclear.
    - ericd 4y ago
      This is kind of interesting: https://www.bts.gov/content/estimated-national-average-vehicle-emissions-rates-vehicle-vehicle-type-using-gasoline-and https://www.bts.gov/content/estimated-national-average-vehic... Exhaust particulate per mile has plummeted over the past couple of decades! By comparison, EPA stoves put out a couple grams of particulate per hour. But, it seems like it's not apples to apples, because brake dust is metal dust, whereas wood smoke tends to be mostly organic compounds. Maybe the body is better at dealing with organic wood smoke compounds? We've certainly been heavily exposed over many generations. Also, seems like there are some efforts to make electrostatic filters for fine particulate in flue gas: https://enervex.com/systems/particle-filter-system-for-stoves-and-fireplaces https://enervex.com/systems/particle-filter-system-for-stove...
ljf 4y ago
Wind and solar need back up yes - but it doesn't have to be from fossil fuel. Currently that is often the cheapest and quickest - but batteries and other energy storage are fast becoming economical. We are already using less non-renewables each year.
- deleted 4y ago
  [deleted]
- vixen99 4y ago
  Fast becoming economical? How fast? Current cost for battery storage I've seen quoted (open to correction) is around $600K per MWh. For every MW of wind or solar power that would be $120 million. Wind farms at around $1.5 million per MW ie., around 80 times that. And are there that numbers of batteries available? Currently dependent on availability of cobalt, lithium,manganese and nickel with China as the main supplier of these and world’s largest producer of graphite, the primary anode material for Li-ion batteries.
  - SuoDuanDao 4y ago
    Batteries are currently following their own version of Moore's law, though they double in quality (or halve in price) every 48 instead of every 18 months. Of course, that isn't a trend that can continue forever, but it doesn't need too many more iterations to be the only game in town.
  - bryanlarsen 4y ago
    8minute energy is building solar plants with overnight battery backup for 4 cents/kWh. https://www.businesswire.com/news/home/20200423005264/en/8minute-Solar-Energy-Expands-Development-Pipeline-to-18-Gigawatts-with-New-Solar-Plus-Storage-Power-Plants https://www.businesswire.com/news/home/20200423005264/en/8mi...
  - seanmcdirmid 4y ago
    Batteries are much cheaper today than they were yesterday, and it’s a clear push downward over time. China being the “main supplier” has more to do with them undercutting everyone else in refining by not paying attention enough to their environment, it isn’t sustainable. All of these raw materials have ample reserves outside of China. Some of battery economy comes from that, but not most of it. There are other ways to store energy than batteries. The Pacific Northwest and even California has a lot of pumped storage hydro capacity. Hydro is a renewable that can be used on demand, and can be combined with other renewables to move water back up to reservoirs.
ZeroGravitas 4y ago
It's not really a problem, even just moving all fossil fuels from heating and transport and using it in electrical generation gets you a 4x gain, from which you lose about 50-60% when turning it to electricity, so still ahead by about 2x even before you start adding in the wind and solar. Plus we already built all that storage for gas and oil, might as well use it as part of the transition.
- FinnKuhn 4y ago
  Additionally with an ever improving grid in Europe local variables such as weather or seasons be can also partially balanced.
  - ZeroGravitas 4y ago
    Yeah, another story covering this had interconnects as just below gas in rank order of usage. Also, despite that large import, UK was a net exporter for the first time in a while last year since France was having issues with its nuclear fleet.
    - stuaxo 4y ago
      We need to get more interconnects between Scotland and England. They are building them, but in the sea which could be interesting with an annoyed Russia. Wind farms were built at sea, on the surface because of nimbyism on land, but being ever cynical I think the real reason was to push the cost and difficulty up giving oil companies more time. Later, during Liz Truss's short and disasterous tenure, just as solar panels were getting very cheap, even very low quality farm land was reclassified as a strategic asset for food to be grown on and no solar. In what was possibly a distraction wind was now to be allowed on land (of course it's much less convenient to put up a wind turbine than to get some very cheap solar panels and that's before all the nimby groups, some of which get dark money funding).
- robertlagrant 4y ago
  > from which you lose about 50-60% when turning it to electricity Does this include transmission losses? I think they average 10% for UK electricity.
Pxtl 4y ago
With what argument? Parent post was talking about measuring energy needs and how efficiency of consumption works, not wind and solar. Did you mean to reply to a different post?

deleted 4y ago

[deleted]

contravariant 4y ago

While that's true you do need to take into account the limited efficiency of power plants as well, especially when it comes to heating. Simply burning gas to generate heat is basically 100% efficient, if you convert it to electricity first you'd need a COP of at least 1.7 to recover the energy lost while generating the electricity.

bryanlarsen 4y ago
A good heat pump has a COP of 4.
- dahfizz 4y ago
  In ideal conditions. Even good heat pumps with COP >=4 will drop below 2 when it's cold out
  - throwaway473825 4y ago
    If it's very cold, yes. But the average should still be well above 3: > Similarly, in Finland, tests of air-to-air heat pump systems from various manufacturers resulted in COPs of 3 at -10C and 2 at -20C. Source: https://www.carbonbrief.org/guest-post-how-the-energy-crisis-is-boosting-heat-pumps-in-europe/ https://www.carbonbrief.org/guest-post-how-the-energy-crisis...
  - bryanlarsen 4y ago
    Judging by how much insulation the typical English house has, it doesn't get cold there.
    - stoobs 4y ago
      Not as cold as the Nordics, sure, but depending on cycles, it can drop a few degrees below freezing between November - March The main issue is that homes were designed to trap and keep heat in, rather than true insulation, which means that as summers get warmer, our homes turn into ovens, with no way to cool them down properly. Case in point last summer with UK temps hitting 40C and above for a few weeks. Government are trying to kill off the old gas boilers though, with heat pumps being pushed very heavily, not sure if they're enforcing it yet or not though. Apparently they're also looking at switching out natural gas for a hydrogen mix, but that means having to rework a lot of the piping/valves as hydrogen needs much higher standards than currently applied.

tpoacher 4y ago

Efficiency is only one aspect of the equation. Storage is another one. As is multiplicity of energy inputs. I still have no idea why nobody uses heat reservoirs for shower hot water, like they do in the Mediterranean. (it's not a sun coverage problem, because contrary to popular anecdotes, the UK actually gets quite decent sun coverage a lot of the time)

ZeroGravitas 4y ago
Main reason is that gas was heavily subsidised and promoted for a bit when they were pumping it from the North Sea. That was obviously short term stupidity at the time, but has only become more so with hindsight. Compare with Norway that also has North Sea gas, but heavily pushed heat pumps and is a market leader.
- makomk 4y ago
  That's not obvious at all. At the time that the UK switched to gas, Norway was pushing resistive electrical heating and not heat pumps - and that only worked for them because nearly all of their electricity came from hydroelectric generation. The push for heat pumps is much more recent, with only a few thousand households in Norway having heat pumps as recently as 2005. The UK doesn't have the geography for that kind of large-scale hydroelectric, and there's a huge efficiency and equipment cost to using resistive electric heating rather than burning fossil fuels directly when your electricity has to be generated from fossil fuels. Also, the coal that cheap natural gas largely replaced in the UK was directly killing a bunch of people by causing pretty nasty pollution. In general, a lot of comparisons with other countries that get published in the British press are like this - they ignore important differences between the UK and those countries or problems and costs associated with what they're doing because the goal is to make it seem like there were easy options that the UK missed out on because our government is evil, not to actually help people understand the world.
  - _oyks 4y ago
    True - and fair point on the UK comparisons. Though of course, sometimes there are easy options that the UK missed out on because they are inept and apathetic, which would vindicate some of those comparisons to some extent.

slashdev 4y ago

When it comes to usage in heating, burning fuel is as efficient as it gets. All the chemical energy (available in that oxidation reaction) is converted to heat. Electricity involves more overheads in generation and transmission.

yrro 4y ago
Some of that heat goes up the chimney. A good quality log burner, used correctly (and I believe that most people who use log burners have no effing clue how to do so) is at best 60-80% efficient. Plus you have to account for the energy used to grow, harvest, season & transport the wood, even before you throw 20-40% of it away when you actually burn the damn stuff!
- nindalf 4y ago
  I think GP might be referring to a gas burning boiler.
  - yrro 4y ago
    Same principle just with a different efficiency number. I doubt any but a fraction of combi boilers are 98% efficient: most people run them too hot, so they aren't able to recover sufficient energy to reach that goal. But in any case, you now have to account for installing and maintaining the gas network, refining the oil into gas, shipping the oil to the refinery, extracting the oil in the first place, exploring for the oil in the first place, and so on. It's far more efficient to burn that fuel to move existing energy from one place (outside) to another (inside)... you can turn 1J of fuel into 4J of heating if you're lucky!
nindalf 4y ago
Burning fuel is pretty efficient, until you realise that heat pumps have an efficiency greater than 1. So a heat pump driven by electricity uses less energy than burning fuel in a boiler. If the electricity is renewable, so much the better.
- 4y ago