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Comment by wepple | Hacker News Reader

This is a bit buried but important:

> And electricity only accounts for 18% of the UK's total power needs. There are many demands for energy which electricity is not meeting, such as heating our homes, manufacturing and transport. Currently the majority of UK homes use gas for their heating

Perhaps we should start talking about what % of “energy” comes from renewables? Probably far more difficult to calculate and we’ll never hit 100% I guess?

View on HN

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.

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

Or a buffer system with batteries - there are a few options that are being researched!

There’s always wood… those stoves have gotten surprisingly efficient, and no new carbon in the carbon cycle, it’s basically a solar battery.

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-bur...

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.

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?

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?

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.

Discounting all the power consumed planting, growing, cutting down and delivery of the logs to the power generator.

We don't have a way to make trees quickly enough. In the timespans relevant to climate change it is far from neutral.

I make no claims it's a global clean energy. Just pointing out it's not actually carbon increasing.

It might be useful to keep in mind that culling trees means that a forest that was in steady state and pulling very little net carbon can go back into more active growth. But I suppose that the total carbon sequestered would be less with a decrease in the average age of the trees.

In a densely populated country like the UK, nobody lives in a remote enough setting for their particulate emissions to not be a concern.

Unfortunately, it seems like middle-class Brits are completely obsessed with log fires, judging by British home renovation shows.

Probably because of British home renovation shows.

Looking at the report that that was based on (page xiv on 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.

This is kind of interesting: 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-stove...

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.

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.

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.

8minute energy is building solar plants with overnight battery backup for 4 cents/kWh.

https://www.businesswire.com/news/home/20200423005264/en/8mi...

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.

China is world leading on renewable production and installation, EVs and EV busses, Lithium, LFP and Sodium battery production, Hydro, HVDC, nuclear, high speed rail and a bunch of other stuff.

It's not just a case of them being happy to dig nasty stuff out of the ground without care. If anything it's because they lack a specific type of nasty stuff to dig out of the ground and so their government hasn't been totally captured by fossil fuel interests.

The west actively abdicated their early lead on all these technologies.

> It's not just a case of them being happy to dig nasty stuff out of the ground without care. If anything it's because they lack a specific type of nasty stuff to dig out of the ground and so their government hasn't been totally captured by fossil fuel interests.

China still produces plenty of coal, so I'm not sure what your point is. I guess you mean oil, and their move into EVs totally makes sense from that context even if they can get it cheaply from Iran and Russia these days.

But the cost is huge. Even the Chinese central government is pragmatic enough to admit that they have a huge unsustainable problem; e.g. https://time.com/6258519/china-lithium-mining-environmental-...

> The crackdown in Yichun, Jiangxi province, follows a local lithium frenzy over the past year as miners raced to feed rampant demand for the battery material — and to benefit from record global prices. Now, they’re grappling with a close-up inspection by environment officials sent from Beijing.

You can tour the Chinese countryside and find tons of places like this.

> The west actively abdicated their early lead on all these technologies.

The west could not keep up Chinese refiners because Chinese refiners have little regard for their environment. As the Chinese central government cracks down and the west worries more about their resource security, the Chinese will simply lose that advantage.

pumped storage hydro, while really cool, are absolutely massive and complicated multibillion dollar infrastructure projects (which California lately has not been particularly famous for)

They were built decades ago, so not a big problem now. The west has lots of places to build these things, it doesn't work out east nor probably in the UK outside of maybe Scotland.

Storage will probably use sodium-ion batteries in the future. Those have none of the four elements you mentioned.

Snowy 2 is $6 billion for 350GWh, so $17k per MWh.

At this point somebody usually argues that you can only do that in Australia and the geography for pumped storage is super rare (I call it the "theres a shortage of up" fallacy), and I have to cite the same study proving that it's actually not.

I would go the contrarian way and suggest Snowy 2 is one of several examples that demonstrate that spending the same amount of money on more renewable generation and some battery storage would provide more reliable power for less money.

Which makes the geography question moot. But most people's intuitions on renewables/battery are years out of date so it's confusing to respond to their sarcastic "are we just going to build lots of batteries, LOL" with "actually yes that's going to be sensible for 80% of the world's population".

edit: long article comparing Snowy to more solar plus batteries:

https://www.solarquotes.com.au/blog/snowy-2-vs-battery-stora...

That's a weird article. It simultaneously argues that between batteries and snowy 2 there is no clear winner, that snowy 2 is a white elephant and that:

>Hornsdale Power Reserve: $690 per kilowatt-hour of storage capacity. If Snowy Hydro 2 comes in at $10 billion, its cost per kilowatt of power will be $5,000, which is 5.6 times more than Hornsdale. But its cost per kilowatt-hour of storage capacity is much lower no matter if you think $20, $29, or $250 is appropriate.

In other words in terms of storing a large volume of energy, cheaply, at high efficiency, pumped storage blows everything else out of the metaphorical water - between 3x and 34.5x cheaper!

I would say that batteries and large scale pumped storage complement each other. I don't agree that Australia will regret building it.

That article is completely mad. But it does admit the following:

  The main drawbacks [of battery storage] are: At the moment, it has a much higher cost per kilowatt-hour of storage capacity. Much shorter lifespan.

  If we consider Snowy Hydro 2’s maximum possible energy storage capacity, it comes to only $20 to $29 per kilowatt-hour

  $5,000 [buys] 5.16 kilowatt-hours of Hornsdale storage

That is, Snowy Hydro is an order of magnitude cheaper for storage.

The article continuously harps on about kW comparisons, and ignores comparing kWh storage: foolish for an article supposedly about electricity storage. For example the article makes the inane point: “If Snowy Hydro 2 comes in at $10 billion, its cost per kilowatt of power output comes to… $5,000 per kilowatt. That’s not cheap. Gas generation normally comes to under $1,000 per kilowatt.”, and again “Snowy 2 Vs. Hornsdale: Assuming Snowy Hydro 2 costs $5,000 per kilowatt of power output, for that cost, we could instead buy . . .”.

Utter rubbish.

> around $600K per MWh

So if enough solar gets built that the electricity price falls to near zero every day, batteries are now cheaper than natural gas?

That's a very impactful change that I honestly didn't see coming.

Even at a domestic scale you can install solar and batteries for your household/heating/car usage -- assuming you have the roof space -- be self sufficent 10 months a year, and have a payack time of about 12 years last time I looked.

The other 2 months a year sure, you've got either grid power or an off grid oil/gas generator.

"$600K per MWh" sounds like the cost per peak (initial) storage capacity; as the batteries can be recharged something like six thousand times before wearing down to half capacity, that's more like adding $100 per MWh ($0.1/kWh) if you throw them out at that point or $50 per MWh (5¢/kWh) if they keep wearing down at the same rate until they're negligible.

> And are there that numbers of batteries available

Not yet — but there are enough people investing in each stage of mining, processing, and making battery factories, that this is probably not going to be an issue.

> 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.

Technically, I think, yes; but that's just where we are today rather than a fundamental property of world geography.

I think you are assuming that turbines would be paired with a certain number of batteries and taken together that would provide continuous power. But that is just not how a grid works or how the economics work. Battery storage is economical because you can buy cheap and sell high. And a system with high renewables penetration will see some very high prices for a few hours or days per month and cheap prices the rest of the time. That is ideal for battery storage, particularly as renewables gets cheaper.

> We are already using less non-renewables each year.

While the UK may be using less non-renewables, they are paying more in total every year for fossil fuels.

Articles like this one (https://www.theguardian.com/environment/2023/mar/09/fossil-f...) shows a rather dark trend.

Some key quotes: From 2020 to 2021 they (fossil fuels) received an extra £1bn support from the government compared with 2020, a 10.7% increase

In 2021, support for fossil fuel extraction rose by 20% to nearly £2bn.

Using fossil fuels as reserve energy is only getting more and more expensive.

Our gov is in the pocket of oil companies, they are perfectly happy for the rest of us to foot the bill for these record profits.

Exactly - and any parts that are from fossil fuel can be replaced over time.

That fossil fuel generation is centralised so easier to mitigate and not where the usage is happening (ie in our towns and cities).

Batteries will make it extremely expensive and we don't even have the technology to do it at scale.

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.

Additionally with an ever improving grid in Europe local variables such as weather or seasons be can also partially balanced.

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.

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).

> 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.

Figure to back this up for anyone wondering: 9% last year: https://www.statista.com/statistics/550583/electricity-losse...

Quote: Every year, the United Kingdom loses a share of generated electricity through transmission. In 2021, transmission losses amounted to around 25 terawatt-hours, or approximately nine percent of the electricity supplied in the UK that year. Transmission losses stood above 30 terawatt-hours in the early 2000's.

Yes it does. A big gas plant is say about 44% efficient (i.e. 56% lost as heat) so 10% of that electricity getting lost in wires takes you down to 40% of the original input energy.

Heat pumps don't qualify for EU Renewable heat incentives if they get less than 2.5 SFP (COP averaged over the year's seasons).

You're possibly thinking of an Open Cycle gas turbine, where we burn gas, it spins the turbine, and the hot exhaust is lost energy. The UK has a negligible amount of this in electricity production and obviously with higher fuel prices there's ever less reason to use that small capacity. The 30GW or so gas turbine electricity in the UK is Combined Cycle, so the exhaust heat runs a secondary steam turbine bringing them up past 50% efficiency.

Well, the storage bit we are a bit bad at, the Tories didn't renew one of the biggest facilities after it closed down which was inconvenient during the Russia thing.

That gas storage facility got closed down because it didn't make economic sense to operate any more - the big summer-winter price swings that made it viable had ceased to exist (possibly because more widespread use of gas for electricity generation caused more gas usage in summer, I'm not sure) and it had physical limitations on how fast gas could be injected and extracted that meant smoothing over those seasonal changes was all it was really useful for. It still didn't even make sense during the whole Russia thing.

Over in mainland Europe, gas storage was vital to dealing with Russia cutting off supplies because their gas infrastructure was physically incapable of importing gas from non-Russian sources fast enough to keep up with winter demand (if I remember rightly, even if they cut back massively on non-essential gas usage). So they basically needed full gas storage just to survive the winter, and of course Russia had made sure it was emptied out the winter before. The UK didn't have this limitation. This need to fill gas storage caused huge problems - global gas demand was already quite high and it takes a long time for supplies to be redirected and high-energy industries to reduce usage, so prices spiked sky-high at first.

As a result, mainland Europe ended up filling its gas storage at close to the all-time-high price and emptying it out when prices were much lower, effectively buying high and selling low funded by extra charges on people's energy bills with the high prices being more or less a direct consequence of the fact that they couldn't just put off buying their gas until winter. If the UK government had done the same, the press here would never have shut up about how much money they "wasted" on it.

Also our sources of gas are relatively diverse and secure compared to some main land countries. The UK maintained supply just fine, the problem was price. And arguably that had more to do with lack of nuclear capacity in France.

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?

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.

A good heat pump has a COP of 4.

In ideal conditions. Even good heat pumps with COP >=4 will drop below 2 when it's cold out

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...

Judging by how much insulation the typical English house has, it doesn't get cold there.

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.

With the high summer temperatures (likely to rise further with climate change), I wonder why more people aren't fitting forced air heating/cooling. That would kill two birds with one stone. Even just a simple mini-split system.

The British seems to like to suffer in the heat. Every summer colleagues laugh at me for having AC units, and every summer they start loudly complaining about how hot it is a week or two later.

Yeah, had to get clued up on this for new house in London. A few points:

1. It is unlikely that hydrogen will be pushed heavily by the UK gov because of the expensive pipe rework. The reason they're pushing hard for heat pumps is because of the Glasgow Climate Pact; they're on the hook to reduce carbon emissions or pay heavy fines. To that extent, subsidising heat pumps becomes financially less unviable for them than doing nothing.

2. Regarding the heat in summer; the houses insulate well but don't do much to prevent heat coming in from the windows during summer. There are some pretty useful half-fixes; mvhrs+insulation, or recessed windows/overhangs/sunshades massively aid this. For those who rent that's not much help though :(

Being from Norway but living in the UK: The average UK house is not built for UK temperatures... Insulation here is a bad joke, at least in older housing.

In the most populated regions of the UK it doesn't realistically go below -5c basically ever.

The average minimum temperature in the winter months in London is 3c above freezing.

London had a -8C night earlier this year

https://www.mylondon.news/weather/london-weather-coldest-nig...

as noted in the article - a once in 12 ish year event. So, 1/4000...

Yeah we'll be fine unless extreme weather events become more common.

But then it’s nasty blackout. Somebody still needs to design electricity grid for one of these very rare events.

Burn some fossil fuels from a "national emergency reserve". Perfect is the enemy of good.

A whole lot of other electricity demands drop massively at night, so while it needs to be planned for, the coldest nighttime period is also the time the electricity grid currently sees the lowest demand.

People are also typically asleep under a ton of duvets. It's not an issue if your home drops to say 10-15c overnight and is warmer in the day.

True. Growing up in Norway I often even preferred sleeping with my bedroom window open during winter.

I'd just whack the wood burner on. It makes sense for people to have a backup.

TBF that's not an option in London, or in apartments.

But - other comments have noted, some backup generation capability that use less green resources should be acceptable for such rare contingencies.

I live in London and used mine in the winter, gas prices were insane.

Probably a good half of our homes have fireplaces and chimneys.

It's not cost effective for everyone to have a wood burner but if only a small percentage used them on the cold days we'd be fine.

People obsess a bit about pollution, as a response to rare events it's fine.

I live in a relatively cold place and my heat pump extract heat from the ground. It's worth it where it's cold.

I did a double take on that claim about outdoor temperatures as I've always assumed people were talking about ground source heat pumps.

In practice or is that what the manufacturers claim?

Either way you should take into account you lose about 40% of that by simply converting the fuel to electricity, which is kind of the opposite of what happens when moving from combustion engines to electromechanical engines.

Depends on operating regime, but newly installed pumps typically are used in a way that gets close to 3.

You can generate electricity with a gas power plant at 50%, use that to operate heat pumps, and you will warm your house more than directly burning the gas.

Or put another way, in a gas dominated grid, switching from gas heating to heat pumps saves carbon gas emissions.

> you lose about 40% of that by simply converting the fuel to electricity

while that is true, it is only a stepping stone towards generating electricity renewably (let's say wind or solar).

The consumer ultimately decides the method (via market forces), and they are the easiest to convert first. If the demand for gas heating drops because of electrification, gas demand would fall (but the cost of extraction remains the same/similar), and therefore, makes electricity cheaper and cheaper.

The losses from current electricity conversion from gas at the plant is merely a short term loss for a better long term 'future', and i would consider it a cost of electrification.

With the most common high-temperature hydronic heating, it's closer to 80% efficiency when running steady-state, and lower than that as the duty cycle decreases (if the system is oversized or for the 99% of the time you're not at the design temp). The remaining energy escapes as hot, uncondensed flue gases. Modulating/condensing boilers can get up to like 95% if you're running with ~100-120F water temperatures, but at that point you can also readily run with an air-to-water heat pump.

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)

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.

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.

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.

> as recently as 2005

That's 18 years ago. Not exactly recent.

The UK had its phase of pushing resistive heating in the 1970s. For a while I had a flat in London that had storage heaters fitted in that period. They would heat up a kind of brick overnight using the off peak 'Economy 7' cheaper rate then emit heat over the day while I was out at work.

What is a heat reservoir for the shower, and what does it have to do with the sun? I'm Googling the term and all I'm finding is standard hot water storage tanks [1].

[1] https://en.wikipedia.org/wiki/Hot_water_storage_tank

https://en.m.wikipedia.org/wiki/Solar_water_heating

Thanks. That's wild, never heard of them before.

Now I am indeed curious what the minimum amount of sunlight required is. I'm sure the angle of the sun is just as important as the duration, on top of weather and seasons and temperatures.

I heard (I know, I know) that solar hot water didn't count towards Kyoto Protocol "credits" so it wasn't promoted, in favour of solar photovoltaic, which did.

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.

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!

I think GP might be referring to a gas burning boiler.

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!

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.

Heat pumps, however, do not work in all climates

The range of climates that heat pumps work in has expanded a lot in recent years. Some modern heat pumps work efficiently down to -20C or lower.

I'd be surprised if there was anywhere in the UK where modern low-temperature heat pumps regularly don't work.

True, I forgot about heat pumps. That’s one of the few times physics let’s you “cheat”.

> burning fuel is as efficient as it gets

Considering this is false as many commenters have mentioned, do you feel any obligation to edit or delete your comment?

Umm, no. I stand by it, although heat pumps hadn’t occurred to me.

But a typical electric heater is probably not going to match the efficiency of a natural gas heater. It matters how much energy is lost in generation and transmission versus extraction and transmission though.

Also I don’t care for your comment. I think if we met in real life, we would not be friends.

No need to guess... If you watch about any talk on climate change mitigation it will start with a chart that shows which sectors use which amount of energy.

It's literally the introduction of the IPCC Report WG3 Report on energy:

https://www.ipcc.ch/report/ar6/wg3/downloads/report/IPCC_AR6...

Just check out the first figures.

Decarbonization of energy use in different sectors will require different technologies, but electricity is key. ENTSOE expects the amount of energy use that is directly electric to rise to up to 50% by 2050 for Europe:

https://2022.entsos-tyndp-scenarios.eu/scenario-results/#dem...

We are talking so much about decarbonizing the electric grid because that's the easy part, but also because its the foundation for what must come afterwards.

Quite. I've tired of pointing out to overly-optimistic responses on the internet about how well countries are doing in this regard, when if you look at the overall energy usage pie-chart, there's a big chunk covering industry and transportation that's a looong way off yet from being covered by renewables.

Not that I wish to be pessimistic, rather realistic.

If electricity prices stay low other forms of energy will migrate.

Already people in the UK are hooking up electric cars and heat pumps to automated tariffs that charge/heat depending on the availability of cheap power (i.e. wind/sun availability).

The important thing is to double down on what is already working.

I heard, just the other day, about someone (in the UK) using their Tesla to make money by buying cheap (night-time) power and selling it back during high-rate times, and I was moved to wonder... Does this "profit" making scheme still work when you take into account the lifespan of the Tesla's batteries -- I'd guess they're good for something like 4000 cycles, and then you're facing the cost of replacement. I have my doubts whether it really works out, but lack the data.

Anyone with insight?

I don't have the numbers with me, but I've seen convincing discussions that it can work with some caveats. The main issue being that spot prices are extremely volatile, so it's possible for a player at the utility space to get very high prices for electricity for very short times. But daytime-pricing schemes, while they follow the general trends of this volatility, insulate the consumer from the worst of this volatility enough that simply arbitraging the difference probably won't pay for the wear on a Tesla. But a fleet of Teslas paying the same rates as the utilities could make it a profitable enterprise.

Reading between the lines of Tesla investor meetings it sounds as though they have the software but haven't implemented it because it would hurt their brand as a luxury good.

Yes, if it gets cheaper people will migrate to electricity and then wind will not be able to be the "main" source of electricity anymore. They'll have to burn more coal or gas. Yay?

Or they'll just keep building solar, wind and power cables to keep up with the increased demand from this transition.

This would be a good thing.

The UK government publishes data on this:

From https://www.gov.uk/government/statistics/energy-trends-secti...

Energy Trends March 2023 - https://assets.publishing.service.gov.uk/government/uploads/...

We don't need to solve everything now.

The headline is still good and doesn't need to be more specific to be good news.

But the headline is very misleading. The article says a third of their electricity comes from wind. 1/3 is not what came to my mind when I read, "main source of electricity." And now knowing that electricity is only 18% of their total energy, that means wind isn't really doing much at all for them. So you can't actually look at this and say, "wow, the main source of electricity! Climate change is nearly conquered! We just need more a few more windmills!" Like many will think when they read this headline.

In which country do you live? At least in Germany heating with electricity is not that common.

I do have separate expectations on electricty vs heating.

The UK does have live gas usage data which includes the amount used for electricity and that going to other uses;

https://mip-prd-web.azurewebsites.net/ (I don't know of a friendlier URL)

>There are many demands for energy which electricity is not meeting, such as heating our homes, manufacturing and transport.

Aka - the big ones.

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