Not sure if Solar is a viable option for car charging. I have a 3.2kw solar array (no batteries) which will kick out a bit over 2 kw when the sun is out but 2kw would take 33 hours to fully charge my car.
Electric cars.
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Trouble with heat pumps is that there's a lot of propaganda around them, and a lot of the antis are basing their arguments on old technology. For instance it was true that they used to only work well down to 5°C, but better refrigerants, inverters etc mean that they can now cope with well below freezing - they get used in Alaska, northern Canada, properly cold places.
For instance, here's one keeping a house at 70-80F at an outside temperature of -27ºF (-33°C) in Minnesota. For comparison the all-time lowest temperature record in the UK is -17°F (-27.2°C) in the far north of Scotland - saying that heat pumps can't cope with low temperatures is pure propaganda. Not all of them can, true - but it's not the absolute problem that some antis try to make out.
I imagine my current tariff is pretty typical in having electricity at 3.9x the underlying price of gas but the Energy Price Guarantee on gas but not electricity distorts the actual price I pay so that it's 6.3x. Whereas if I had electricity at the 33p mentioned above it would be just over 3x the price of gas even net of EPG.
And we're getting to the stage that now our electricity system is significantly decarbonised, all the green taxes are going to move from electricity to gas, shifting the balance further in favour of electricity.
But in a world where the UK only produces half the gas it needs (and production is declining), the question should really be rephrased. In the last decade we've imported 402TWh of gas in an average year. Where will that much gas come from in future, and how much will it cost?
If the last year has taught us anything, it's that we need to think seriously about energy security and producing as much of our own energy as we can, because we can't rely on the international market being able to deliver the amounts we need, at a cost that won't trash the economy.
For instance, here's one keeping a house at 70-80F at an outside temperature of -27ºF (-33°C) in Minnesota. For comparison the all-time lowest temperature record in the UK is -17°F (-27.2°C) in the far north of Scotland - saying that heat pumps can't cope with low temperatures is pure propaganda. Not all of them can, true - but it's not the absolute problem that some antis try to make out.
Propaganda based on old technology. Yes efficiency goes down in colder weather, but what matters is the average efficiency through the year. I know someone who on average, through the year, is getting 3.2kWh of heat for every 1kWh of electricity he puts in (CoP=3.2 in the jargon). Compare that with a gas boiler that gives maybe 0.9kWh of heat for every 1kWh of gas you put in, so you need your electricity price to be less than 3.55x your gas price for it to break even at the fuel level.
I imagine my current tariff is pretty typical in having electricity at 3.9x the underlying price of gas but the Energy Price Guarantee on gas but not electricity distorts the actual price I pay so that it's 6.3x. Whereas if I had electricity at the 33p mentioned above it would be just over 3x the price of gas even net of EPG.
And we're getting to the stage that now our electricity system is significantly decarbonised, all the green taxes are going to move from electricity to gas, shifting the balance further in favour of electricity.
But you already get your gas boiler serviced, right? And if you're worried about Legionnaires’ disease then you should be really worried about carbon monoxide poisoning given that you are more likely to die from carbon monoxide than Legionnaires’ (40 per year from carbon monoxide in England & Wales, versus a 2007-16 median of 32 from Legionnaires', of which 75% had underlying conditions like heart disease etc). And Legionnaires’ disease is not specific to heat pumps, the bacteria can grow wherever there's hot water.
You only need the big radiators because the flow temperature of traditional heat pumps is rather lower than gas boilers. But you're now starting to see high temperature heat pumps that can have flow temperatures in the 70-80°C range output by gas boilers, so you don't need to change radiators. Comes at a slight hit to efficiency, but you make that up by saving the cost of replacing your rads.
That was the right question 20 years ago, when the UK was self-sufficient in gas. But for one thing, renewables are producing electricity cheaper than gas - way cheaper at the moment, but even if you start plugging in "normal" prices for gas then it's starting to look like it's still more expensive than even renewables + storage.
But in a world where the UK only produces half the gas it needs (and production is declining), the question should really be rephrased. In the last decade we've imported 402TWh of gas in an average year. Where will that much gas come from in future, and how much will it cost?
If the last year has taught us anything, it's that we need to think seriously about energy security and producing as much of our own energy as we can, because we can't rely on the international market being able to deliver the amounts we need, at a cost that won't trash the economy.
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Average mileage in 2019 (last pre-Covid year) was 6607 miles for cars, so 18.1 miles per day. Something like an ID4 gets 175 miles range from a 55kWh battery, so 3.2 miles per kWh. 1 hour of charging at 2kW adds 2kWh of charge which is 6.4 miles of range.
So you'd need 2h 50m of charging at 2kW to add range equivalent to the average UK daily mileage.
Obviously it will vary depending on your pattern of usage, if you empty the tank on successive days then it won't work, but it's doable.
My wouldn't touch with a bargepole comment was due to the upheaval, imagine having to have all the current underfloor pipework and all radiators replaced and having to find space for a water tank and huge noisy box in the garden or yard.
We don't know how often or how much this is going to cost.
I doubt Mt 25 year old radiators will be up to the job and the whole house is still going to need all the pipe work replacing.
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Why would radiators suddenly not be up to the job? It's the same water, at the same temperature, from the house plumbing POV a high-temperature heat pump would be no different to fitting another gas boiler. So "all the pipe work" would only need replacing if you would be replacing it for a new gas boiler. Just FUD.
Again - the pipework and rads wouldn't need replacing with a high-temp heat pump.
The water tank thing could be a problem for the ~50% of houses that don't have them, although it tends to be more rental properties that don't have them whereas owner-occupied are more likely to have them. But there's still plenty to be getting on with, and I guess we'll have to see if technology comes up with a way of doing without a big hot water tank.
The box is no different to having an aircon unit which is perfectly common in many countries - and modern units shouldn't be noisy if fitted properly, you heard how little noise that one in Minnesota was making even running at full chat below -30°C.
I don't know how much it's going to cost to get my car through its MOT this year, that doesn't stop me owning a car.
It's nothing too weird, they don't fill up the pipes with champagne, it's little different to servicing an aircon unit and checking the pipework on a gas boiler.
I can see the point you are trying to make but the overall technology and hardware I have doesn’t make it viable for me.
My charger charges my car at a rate of 7.4 kwh. My solar array in a best case will only kick out around 2 kwh so there’s an excess of 5.2 kwh that I’m importing at 33p kwh. It’s far less hassle, and a lot cheaper, to just charge the car at night on my 10p kwh rate.
Yes, I could temporarily limit the car to just 2kwh charge rate but every time a cloud passes or the house starts eating into what I’m generating, I start to import expensive electricity.
![BREWING THERMOMETER STICKERS ACCURATELY MONITOR FERMENTING BEER & WINE LIQUID TEMPERATURES 5PCS HOME BREW SPIRITS WINE LCD ADHESIVE [US]](https://m.media-amazon.com/images/I/311DDjo2X3L._SL500_.jpg)
Here is video 2 this is 12 months old and this guy said in the first video he would have one now if they were any good and he still doesn't have one so he is not an anti putting them down.
Can you use your existing system and just replace the boiler with a pump - NO.
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It's a bit of a leap from "my various bits of hardware aren't smart enough to talk to each other" to :
All you're missing is something that can talk to the solar to see how much is being generated, talk to the meter to see how much is being used by the rest of the house, and then talk to the car charger to say "at the moment you can use "X" kW as that's what's left over". It's not rocket science, I imagine there are people out there that have hacked together something with a Raspberry Pi or something - given the amount of money that could be saved there's a pretty good incentive to get that sort of thing fixed.
But it doesn't invalidate the concept of solar charging in principle.
I have quite a sophisticated HA system in place already. I can connect a switch to my 3 pin plug sockets and set it so that It will only be “on” if the amount of energy generated is more than that being consumed. In fact, I have one already. We plug our phones, laptops etc into it so they only charge on free electricity. But, if you plug a car in and all of a sudden the power shuts off, as would be the case here, it thinks there’s an error and won’t automatically charge again when the power comes on without unplugging the charger and plugging it in again.
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The best propaganda pretends to be independent, pretends to be on your side. And this guy has more followers than subscribe to the Daily Mirror and Daily Express put together, a YouTube channel with 500k followers is a media business with serious influence and making >£100k a year.
And once you've reached that level, it becomes seductive, and you find that saying "yeah - it's OK, but the best way forward depends on your particular circumstances and I can't make that decision for you on YouTube" makes *far* less money than getting angry about things and talking about "Heat Pump CONSPIRACIES" and the like. You've seen it with some of the Covid people, some of whom like John Campbell may have started with the best of intentions but soon find that the dark side is far more profitable - I've seen estimates that Campbell was earning £50k/month at one stage as he went more and more anti-vax etc.
In fact if you want to talk about conspiracies, you might want to look at the very rich companies and people with a big vested interest in keeping Europe hooked on gas boilers - heat pumps are the biggest threat to the £multi-billions that Gulf countries make out of selling gas. If you were them, wouldn't you do everything you could to stop heat pumps? In that context £10k here or there to social media influencers could be money very well spent.
Once again, if it's a high-temperature heat pump - YES.
Agreed with your point about propaganda.
Can't agree with the point about being seduced by money, that's an opinion rather than a fact.
Dr John has always presented his sources to let us decide. I'd imagine when you produce as much stuff as he does there are bound to be a few duds in all that content. The mice / bi-valent testing or lack of it was an eye opener for me.
I'd agree that it is in gas producers interests to keep us on gas - that just makes sense - do turkeys vote for xmas?
Until an effective new proposed solution becomes cheap enough for a ROI under 10 years its is just a deterrent for me and many I know.
Looks like we are drifting from electric cars to general electric power consumption & heat pumps. Wasn't there another thread for that somewhere?
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However well-intentioned Campbell was when he started, he now seems to have well and truly jumped the shark, and preserving an income of £50k/month would be a plausible reason why that might have happened. To give you an idea of how real virologists view him, here's Stuart Neil, professor of virology at King's London
"John Campbell oscillates between dribbling idiocy and criminal medical disinformation without pausing for breath"
It takes far more time to debunk individual claims that it does for him to make them, but again to give you a flavour of how he gets things wrong :
https://healthfeedback.org/?s=Campbell
Same with Michael Yeadon who was held up as an expert at the start of the pandemic because he once worked for Pfizer, but is now saying that respiratory viruses don't exist and Spanish flu wasn't influenza. He's gone quiet on the "Covid vaccines will kill everyone within 2 years of getting jabbed" though, can't think why.
Centrica (British Gas) announced in October they would offer a 7kW pump with 200l hot water tank for £4,999 with 5 years interest-free credit. That's now turned into a retail offer of £499 in Scotland and £2999 in England/Wales after subsidies, which are higher in Scotland.
Anyway, getting back to electric cars, Gul-e are offering cable runs cut into the pavement to remove trip hazards from on-street charging :
That is fine if you can park outside your home here it's a fight every day for a parking place as there are more cars than spaces.
A few police cones Joey Boswell style will sort that out
Yes, I can set the car to only accept 10a and the charging slows to about 2kw, or 5a the charge at about 1kw. But, if you cut the power to the car, as would be the case if the house stopped generating excess electricity in this example, the car throws up a “Charge Error, No Power” fault and won’t start charging again unless you disconnect and reconnect the charge cable.
That can all be monitored and controlled via the API;
https://www.teslaapi.io/vehicles/commands
Excess Power from solar > say 0.5kW then set car charge Amps to kW value x 4 and start charge. If excess power falls below 0.5kW stop charge. Monitor and modulate charge Amps as available excess power changes, in real time.
Again, I'm only familiar with the Tesla API, your milage may vary with other marques.
It could get pretty complicated integrating different cars, chargers, import/export metering protocols etc. on one platform starting from scratch but it's all perfectly doable, with currently available hardware it just needs either some plug and play industry standardisation to make it easy, a good integration engineer or a very dedicated DIYer.
