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Cont: Electric Vehicles II

acbytesla

Penultimate Amazing
Joined
Dec 14, 2012
Messages
36,493
Continued from here.
Posted By: Agatha



I don't think you'll be happy with the maths.

My car typically takes 10 kWh to charge.
I have 8 188W solar panels, which generate, on average, about 5 kWh per day.

Hence, it would take at least two full days to charge my car.

Note that a 10kWh battery is tiny compared to modern all electric vehicles.
Two full days of solar panel output gives me 45 km of range.

The current Nissan Leaf has a 40 kWh battery, hence eight days to charge from my current eight panels.

I think you can currently buy 300 W solar panels but you'd still need a lot more than one to charge an EV.


Ideally, you'd put something up like a hay shed (or carport) with a sloping roof to maximise your solar collection. I was lucky, my roof slope is within a degree of ideal for this latitude.

I recently purchased for a friend 24ea 430w panels at $175ea at SanTan Solar. They have great deals there all the time. They sell new and used panels. Right now you can buy a pallet of 25 435w Sun Power panels for $3,000.

Having a shed can be convenient, but you can also build a rack. that's what my friend did. Actually he built three all out of lumber from trees he cut down from his property. We even build a tilting mechanism so he could change the tilt angle a few times a year.
 
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I don't think you'll be happy with the maths.

My car typically takes 10 kWh to charge.
I have 8 188W solar panels, which generate, on average, about 5 kWh per day.

Hence, it would take at least two full days to charge my car.

Note that a 10kWh battery is tiny compared to modern all electric vehicles.
Two full days of solar panel output gives me 45 km of range.

The current Nissan Leaf has a 40 kWh battery, hence eight days to charge from my current eight panels.

I think you can currently buy 300 W solar panels but you'd still need a lot more than one to charge an EV.

Ideally, you'd put something up like a hay shed (or carport) with a sloping roof to maximise your solar collection. I was lucky, my roof slope is within a degree of ideal for this latitude.
Yes, that's part of the problem. Around here plenty of people are putting up pretty substantial solar collectors, but my buildings are unsuited for that (old house with slate roof, outbuildings all point the wrong way, etc.), most of the land on a north-facing slope, so I'd have to put something up in a field, and the whole thing would be expensive. Charging stations have arrived in the region, including towns where I shop, so that helps. But so far, the whole thing has not been either economical or urgent enough to warrant the cost, given that at least for a while still I have a dirt-cheap little car that gets good gas mileage.

It's interesting to speculate, though.
 
If my yt feed has anything to say the conversion kits for existing vehicles is becoming a lucrative market. That's good news for those who desire the old Camry, a hybred/electric and be free of limitations like Tesla imposes.
It seems even Chevrolet is on this now.

Progress in even grassroots efforts is making the EV revolution happen.

Last week in the body shop we had a hybred Camry and Prius parked side by side, a year ago that wouldn't have happened. I am liking the new look.
 
If my yt feed has anything to say the conversion kits for existing vehicles is becoming a lucrative market. That's good news for those who desire the old Camry, a hybred/electric and be free of limitations like Tesla imposes.
It seems even Chevrolet is on this now.

Progress in even grassroots efforts is making the EV revolution happen.

Last week in the body shop we had a hybred Camry and Prius parked side by side, a year ago that wouldn't have happened. I am liking the new look.

They're available in the UK for classic cars, but the cost is pretty darn steep and quite honestly I reckon they eviscerate the cars involved. If we're going to have electric cars I'd rather have the likes of the vw electric bus. It makes no bones about being sporty but provides sensible transport for those who want it - just like the original.
 
When a classic is beyond a certain stage of restoration there is no shame in making it a fun driveable car.

The farms of the US are awash with "classic" cars stripped of engines and such, rotting out slowly, that could be made safe daily drivers again.
Purists may find a rare options version that could be worth millions if the original engine and whatever could be found. Until then it's still a junk old car.

Have some fun with your dream car and get the benefits of a modern drivetrain. For many it's close enough and avoids the costs of driving a gallons per mile car.

Oh, true, some of the trashed relics missing everything but a rusted out body shell and maybe the back axle might well be good subjects for electric drivetrains, but those aren't classics I'm talking about.

And the idea of a modern electric drivetrain in a classic car fills me with horror. I'm quite capable of enjoying a classic car as it was designed and built.

One pedal driving an e-type jag for instance?

Shudder.
 
An old Austin or Mini is basically a cheap low end car that wouldn't be shamed by the conversion. A mint RR Silver Ghost probably would be.

I watch a bit of banger racing and it's obvious that any old car out of inspection is fair game for wanton destruction. Trying to keep one within MOT regs by making it electric seems more noble.
 
An old Austin or Mini is basically a cheap low end car that wouldn't be shamed by the conversion. A mint RR Silver Ghost probably would be.

I watch a bit of banger racing and it's obvious that any old car out of inspection is fair game for wanton destruction. Trying to keep one within MOT regs by making it electric seems more noble.

I know someone who wanted to convert an old mini here in Australia.

He's given up on the project because the bodies are so incredibly expensive.

(In his case, he was looking for a mini van, because the stub axles at the back made a space which was ideal for housing a big battery tray.)

Saw a flash old VW combi the other day that had been converted. (One of the campers with barn doors) It looked like a new car, and I was jealous.

Also find myself wanting to buy one of these:

https://morris-commercial.com/morris-je/

No idea why, best guess is that it resembles a toy that I had as a child (but can't remember).
 
The one that left me wanting was a 1965 Ford F100 4 by 4. With two big batteries it was pretty much the same power rating as the V8, about 200lbs heavier and about the same distance on battery as the gas engine on one full tank.
(My 1978 F250 with a 351 V8 would go 100 miles max on a tank. Seems a standard for the vehicle.)

Bottom line, a vehicle that would serve my needs and uses parts I can get anywhere . I wouldn't be afraid to put it in a situation it could be damaged by hauling stuff.
 
I've had a few old VW buses (though mine were later, a couple of 71's, a 73 and a 75, three of them pop top campers, plus a couple of '72's for parts). Nice in their way, but I'd never want one now. About the only thing worse in a crash is an Isetta. My last one, a '73 with partially removed interior, was a running car, but I refused to give it to any of my kids. But for electric conversion they'd not be bad. Lots of room - you could just put a big battery under a false floor in the middle, and the weight would be in the right place. And they were rated to carry a ton of cargo already.

I like the idea of electrifying some older cars, especially ones that had some charm or some features that I miss. But around here, the enemy of cars is more likely rust than wear and tear. The conversion business makes more sense in the south, where you'll find intact bodies. Here the woods are full of vehicles that are no longer roadworthy but mechanically sound. I've had to toss or sell several vehicles over the years that had many miles left in their drivetrains, but rusted too badly to stay on the road.
 
The one that left me wanting was a 1965 Ford F100 4 by 4. With two big batteries it was pretty much the same power rating as the V8, about 200lbs heavier and about the same distance on battery as the gas engine on one full tank.
(My 1978 F250 with a 351 V8 would go 100 miles max on a tank. Seems a standard for the vehicle.)

Bottom line, a vehicle that would serve my needs and uses parts I can get anywhere . I wouldn't be afraid to put it in a situation it could be damaged by hauling stuff.

There seemed to be similar standard here.

Pretty much every passenger car would have a fuel tank that would allow a trip from Adelaide to Melbourne without filling up (IIRC). (726 km/450 miles). NB. My current car doesn't do that, it has a max range of 550km with a full tank and battery. (I don't think SUVs were expected to have the same range, and mine has a fairly small fuel tank).
 
The VW air cooled vehicles were always a first option for conversion. The vans offered open floor space that is easy to work with. The cars were dirt cheap for years, not anymore however, because the engine was usually junk.

Not a favorite of mine for a few reasons but as commuter cars go they are ok. The Smart car would be a better option but they already do an electric version.
 
An old Austin or Mini is basically a cheap low end car that wouldn't be shamed by the conversion. A mint RR Silver Ghost probably would be.

I watch a bit of banger racing and it's obvious that any old car out of inspection is fair game for wanton destruction. Trying to keep one within MOT regs by making it electric seems more noble.

The classic mini was certainly cheap and low end, but outgrew that description to become icons by being fun to drive and cool. I own two and am quite happy to keep the ICE engines because they remain above all fun to drive. I have no need for anodyne electric power. There are conversions available which cost way more than any but the most expensive restored minis around.

The VW air cooled vehicles were always a first option for conversion. The vans offered open floor space that is easy to work with. The cars were dirt cheap for years, not anymore however, because the engine was usually junk.

Not a favorite of mine for a few reasons but as commuter cars go they are ok. The Smart car would be a better option but they already do an electric version.

I agree with the combi because it was never considered fun to drive. Iconic, yes but only because of being the transport of choice of the hippie generation.

Hence my preference for the VW ID Buzz. Based on an Icon, but no pretention of being any sort of sports car.
 
Back for the moment to old VW's, the fragility of the "upright fan" aircooled engines made beetles and earlier buses a prime candidate for electric conversion, since they'd often suck a valve at around 40 thousand miles and need a new engine. A few hardy pioneers re-powered old beetles with golf cart or forklift motors.
 
It was the closest chassis and a very simple vehicle compared to today. Add in convenient fatal flaw a low price tag it's fair game.

The Tata Nano is it's closest current equivalent now but won't meet safety standards in many places. I understand Tata already makes an E-version.
That is what would serve my family needs right about now.
Even if my wife thinks she needs something more like a VW Jetta, and a chauffeur.
 
We have a new business right next to my shop that uses google blood money to convert gas cars to electric. Theyre really learning as they go and doing some amazing work. I'm super excited as they bring in CNC machines, laser cutters and other goodies that are just perfect being next to a music school where the kids may want to make guitars.

They had some potentially scary mishaps and growing pains (accelerator pedal wired backwards!) but its all part of the fun. Some pretty amazing stuff

Their VW van conversion is pretty epic so far. I'll see if I can get some pictures today
 
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In the interest of saving you a click:

For its part, the Marine Corps maintains it still has no requirement for an all-electric tactical vehicle, preferring to invest in fuel-saving retrofits and cautiously develop a hybrid truck while waiting for technology to mature.

[...]

The Army doubled down on the challenge, publishing its own climate strategy the same year with a 2035 deadline to field purpose-built hybrid tactical vehicles and a 2050 target to field fully electric tactical vehicles.​
 
Another EV story on the BBC. Nissan are being accused of "Dumping EV pioneers"

I thought it would be about some fundamental technical shortcoming which was leaving drivers stranded but instead it's an issue with their phone-based app:

The firm says the app - which allows remote control of functions such as heating - is stopping because the UK's 2G network is being switched off.

But customers have reacted with anger, telling the BBC they did not expect it to be withdrawn.

And how many people are affected ?

Around 3,000 Nissan Leaf and e-NV200 cars made before 2016 are affected by the app being withdrawn.

These older vehicles are fitted with 2G control units which communicate with the app.

The media sure loves an EV scare story :rolleyes:
 
"things stop working on old cars - shock"

Also, that original app is rubbish. It doesn't work at important times like on cold mornings when you want to press heat your Leaf. "Luckily," my infotainment system failed and they replaced it with the newer version on my Leaf 2 or I'd be facing losing the app.
 
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Another EV story on the BBC. Nissan are being accused of "Dumping EV pioneers"

I thought it would be about some fundamental technical shortcoming which was leaving drivers stranded but instead it's an issue with their phone-based app:



And how many people are affected ?



The media sure loves an EV scare story :rolleyes:

A foretaste of things to come perhaps rather than a total disaster right now.
 
Although I agree that the article is more of an anti-EV hatchet job than a legitimate story since non-EV vehicles were also affected when 2G (then 3G) service was phased out, it is a bigger problem for EV owners.

When the 3G network shut down, my BMW i3 lost connectivity like some non-EV BMWs. But it was a somewhat bigger deal for the EV owners because the cell phone connectivity provided real-time updates on public charger locations to the car's navigation system.

Of course, there were alternatives like using the PlugShare app and, over time, updates like that became less critical. But the loss of connectivity was still a bigger deal for EV owners than ICE owners.

As much as I loved that i3, I am very disappointed in BMW for not standing behind it's owners. A few people had demonstrated that the car could easily be upgraded to 4G. But BMW refused to offer an upgrade or support those that did it themselves. On top of that, I had prepaid for connectivity and did not get a refund.
 
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"things stop working on old cars - shock".

But "stop working" isn't the same familiar thing as old things breaking, it's things becoming obsolete and unsupported so they can't be fixed. Cars, products with a 15+ year life, now integrate with tech which has maybe a 5-10 year life. (What do you mean I can't get an updated CD ROM for my car's navigation system?)

Even when you're not talking about integrating with external technology, there are new vulnerabilities, with more repairs so expensive that a relatively young car can get written off. A friend's BMW i3 stopped charging from its range extender. Ultimately the problem will be something simple, but it's not economic to track down that simple thing. The repair procedure (do this test and if it fails change that entire unit) would have cost most of the value of the car. After some time it spontaneously started working again. Now he's crossing his fingers it keeps working so he can sell it, caveat emptor.
 
A foretaste of things to come perhaps rather than a total disaster right now.

If it is, it's a foretaste for everyone, not just EV owners.

Many new cars, irrespective of propulsion system, have features that rely upon connectivity which in turn relies on access to mobile data. Other features rely on receiving updates (whether it's updated maps for the navigation system or firmware updates). If manufacturers choose to no longer support those features then they will become obsolete (like Windows 3.1).

Of course you can continue to run without receiving updates but there's a non-zero risk associated with that.
 
My current petrol car no longer gets map updates as Mercedes have changed the system, and I don't get Apple CarPlay on that model. I can pay for access to maps on their website, put them on a memory stick and upload them to the car, but it's easier and cheaper just to use Waze on the phone.

Anyway, I ordered a new EV car today - 18 weeks build time - so not much longer with an outdated system, at least until Skoda withdraws access to Apple CarPlay or something.
 
If it is, it's a foretaste for everyone, not just EV owners.
This is why I will stick with my 2011 Leaf for the foreseeable future. Who needs all that stuff?

The navigation system on my imported Leaf is stuck in Japan and I can't be bothered paying to get it changed because I wouldn't use it anyway. The car doesn't have any of these fancy 'self driving' features, or even battery thermal management - so there's much less to go wrong. It doesn't need (or can do) over-the-air software updates, so no chance of being 'bricked'. There are some buttons on the steering wheel that I don't touch, and all the car settings are in Japanese so I don't touch them either.

Range on my Leaf is only about 50 miles so I won't be going on any road trips, and the tired old battery can't handle fast charging so I will never do it and therefore don't need to know where the fast chargers are or whether they work. I just take my 2kW cable with me and plug it into a normal mains socket if I need more juice.

Once the battery gets too tired I will replace it with a fresher second hand unit. This will cost much less than buying a new car, and I won't have to put up with all the fancy features they insist on putting in them. Of course this assumes that the car will still be in good condition by then, which is pretty likely because without the vibration and mess of a gas engine and my careful driving it should easily last another 10 years. It also assumes that I will still be fit to drive - which isn't a given when you are pushing 70.

Of course you can continue to run without receiving updates but there's a non-zero risk associated with that.
Just kill all connectivity and then you won't have to worry about being hacked. :)

Funny thing is I have numerous devices that didn't get the latest software update and they still work fine. This computer I'm typing on right now hasn't had an update in years because they dropped support for 32 bit machines.

I reckon if your car is working fine then you don't need updates. Take the latest Tesla 'recall' for example. NHTSA said they had to make the text larger on the brake icons, so what did they do? Nixed the icon and just made it large text only. Yuk! Can't do that on my Leaf because the icons are old-school illuminated stencils. :cool:
 
I have been considering an EV for some time. We have a perfect good (actually better than good) Subaru SUV, but don’t do a lot of miles any more.

With the current state of technology and limited government subsidies in Australia my calculations show a break even point after 8-10 years. Approaching our mid 70s, we will be keeping our Subi.
 
I have been considering an EV for some time. We have a perfect good (actually better than good) Subaru SUV, but don’t do a lot of miles any more.

With the current state of technology and limited government subsidies in Australia my calculations show a break even point after 8-10 years. Approaching our mid 70s, we will be keeping our Subi.

The next car I buy will almost certainly be an EV but I intend to run my current whip, a 2016 Skoda Oktavia, into the ground before I buy one. Ideally I'll get another 5-10 years out of it and by then we may not even need two cars.

My obsession with minimising our electricity consumption has however clouded my judgement when it comes to using Mrs Don's EV. In the summer we can charge it for free given halfway decent weather but it's a different matter in a Welsh winter. In order to limit our electricity purchases on dark and cloudy days I've been using the Skoda instead.

The stupid thing is that we now have a tariff where we get (for the UK) cheap electricity for 4 hours overnight (9p/kWh vs 28p), the kicker being that we pay a premium (30p/kWh) for the other 20 hours. Even at the expensive rate it costs less than 8p/mile to fuel the EV (as opposed to around 15p/mile). It's under 3p/mile at the cheap rate and - due to our ridiculous electricity supply arrangement at Don Towers - we can get around 60 miles of range into the car during cheap hours.
 
The next car I buy will almost certainly be an EV but I intend to run my current whip, a 2016 Skoda Oktavia, into the ground before I buy one. Ideally I'll get another 5-10 years out of it and by then we may not even need two cars.

My obsession with minimising our electricity consumption has however clouded my judgement when it comes to using Mrs Don's EV. In the summer we can charge it for free given halfway decent weather but it's a different matter in a Welsh winter. In order to limit our electricity purchases on dark and cloudy days I've been using the Skoda instead.

The stupid thing is that we now have a tariff where we get (for the UK) cheap electricity for 4 hours overnight (9p/kWh vs 28p), the kicker being that we pay a premium (30p/kWh) for the other 20 hours. Even at the expensive rate it costs less than 8p/mile to fuel the EV (as opposed to around 15p/mile). It's under 3p/mile at the cheap rate and - due to our ridiculous electricity supply arrangement at Don Towers - we can get around 60 miles of range into the car during cheap hours.

I get this. Cost of electricity should not be much of an issue for us though. We will have solar panels installed in a couple of weeks and it looks like we can charge nearly the whole year. It’s the capital cost. The EV version of the Subi we own comes in at around $A90K, or twice the cost.
 
Captain Obvious here.

It usually makes better economic sense and is usually better environmentally to keep your current car as long as possible.

But, we often have other reasons for buying a new(er) car. I bought our newish EV during a faux midlife crisis almost exactly 20 twenty years after buying our Mustang GT convertible. And I bought it for the same reason. Chicks dig white-haired guys driving cool cars. (At least that's what my wife says.)
 
I get this. Cost of electricity should not be much of an issue for us though. We will have solar panels installed in a couple of weeks and it looks like we can charge nearly the whole year. It’s the capital cost. The EV version of the Subi we own comes in at around $A90K, or twice the cost.

You're right, EVs are currently considerably more expensive than their ICE equivalents when comparing similar models from the same manufacturer. The comparison may not be quite as bad as it first appears given that EVs tend to be better specified, but if you don't want the extra bells and whistles then that's not really a selling point. :o

The price differential is expected to close significantly in the next few years and you can currently close it significantly by buying a nearly new car. Neighbours of ours have just bought a couple of months old Skoda Enyaq for a little over £30k which is about the same price as a new large (for the UK) SUV. I certainly won't be buying a new EV - in the same way as I haven't bought a new ICE since 1998.

Regarding your PV panels, are you also getting a battery ? Are you able to sell any surplus back to your electricity supplier ?

We found that, even in the summer when we had plenty of surplus, without a battery we were still typically using 3-4 kWh a day to cover "phantom load" and short periods where demand exceeded generation. We now have a battery installed and we're making better use of the solar (though it's very early days and the weather hasn't been great) and the battery also allows us to buy in cheap electricity overnight if we have little or no generation and use it later in the day.
 
I've considered installing just enough solar to offset my EV's electrical use - not for economic or environmental reasons but just because it would be cool. But just now was the first time that I sat down and did a rough calculation of how much solar capacity I would need. I drive less than 300 miles a month and average about 4 miles per kilowatt hour. Using an online calculator, I found that I would need panels rated for 700 watts taking up about 45 square feet. The panels themselves wouldn't be too expensive, but the cost for a controller and inverter would make it impractical.

I thought that maybe I could justify it in my situation because our car can act as a battery backup if the power is out after a hurricane and we live in a rural area where hurricanes are not uncommon and it can take weeks for power to be restored. But if my math is right, a small solar setup like that would only add about a day to the amount of time that our car could power our refrigerator, TV, internet, a light, and a fan.
 
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Regarding your PV panels, are you also getting a battery ? Are you able to sell any surplus back to your electricity supplier ?.

As with EVs, batteries are not viable for a household of 2. It would cost $A10k for a decent one. Hopefully technology and government sbsidies will make them affordable in future.

In Australia our domestic solar program has become so successful that suppliers simply don’t need any more solar. The feed in tariff is about 4 cents per kWh. Almost nothing. In fact I recently heard the power generator covering our region no longer offers anything, but I will soon find out.

What the solar panels will do, provided we are disciplined about when we use devices, is to drop our bill by about 70%.
 
As with EVs, batteries are not viable for a household of 2. It would cost $A10k for a decent one. Hopefully technology and government sbsidies will make them affordable in future.

In Australia our domestic solar program has become so successful that suppliers simply don’t need any more solar. The feed in tariff is about 4 cents per kWh. Almost nothing. In fact I recently heard the power generator covering our region no longer offers anything, but I will soon find out.

What the solar panels will do, provided we are disciplined about when we use devices, is to drop our bill by about 70%.

That low level feed in tariff is quite usual here in the UK and many suppliers simply don't buy excess. :mad:

Our finding regarding PV and battery are that PV only reduced the amount of electricity we bought by around 50%. The limitations were:

  • The house uses around 5kWh per day to just keep ticking over. On average about half of this was covered by PV but in the winter we often generated close to zero.
  • Our oil-fired central heating adds around 400 watts to the demand when it is running. Unfortunately it runs most at night, in the winter, when the PV cannot provide energy.
  • Peak usage, for example cooking using the oven and a couple of rings on the hob, exceeded the PV's ability to generate AND
  • Our usage didn't necessarily align well with times when a lot of solar was available. For example we would use an electric dryer on cold wet days when there was little or no solar generation

Our investment in a battery will likely reduce our consumption by a further 25% and our expenditure to 10%-15% of what it used to be. Payback will likely be in 8-10 years and there aren't many investments out there with that kind of yield. The savings will come from storing PV generation for later use (like in the past two sunny days) and also by making use of cheap overnight electricity to charge the battery and then use that during the day to run the house when there is little or no solar generation. The case is made better by the UK's ridiculously high electricity costs (25p-30p per kWh).
 
If you're in the UK, and have an EV, it's a good time to renew your road tax, even if it's not due. It goes up from zero to £180 in April 2025. If you renew now, you should be able to renew for zero in March 2025. I've done mine; it takes a couple of minutes, you just need your V5 and go to https://www.gov.uk/vehicle-tax
 
BYD ( of spotty QC according to the internet) is negotiating building three factories in Mexico as the US car industry is preemptively blocking them.

They don't want cheap Chinese electric cars flooding the market before they can manage to figure out how to sell their own.
And I understand some safety concerns over fires too but it screams of just keeping BYD out because they can't figure it out and don't want to hustle to do so.

These cars will have to pass US crash test and all safety standards before being submitted of course.

The ones at the local dealer in town are imported from China now and pass Mexican standards, mostly. They are probably some of the unsold overstock from last year.
I wouldn't judge future factory production if it happens from those. But they are here now.

It's a low effort market test here as the showroom has space for four cars and looks rented out.

They managed to make the three wheeled motorbike based taxis legal here and the cargo trikes. Those are death traps. With any luck a car body with actual safety features can make the cut.

With BYD already in Brasilian markets they may not see the needing investment in Mexico if the northern markets are closed. That would be another hit for the possibility of growth here.
 
The Toronto Star takes on EVs in Winter.

Watch: An electric road trip visiting Ontario's cleantech future

Toronto Star photographer Steve Russell and climate change reporter Marco Chown Oved went on a road trip through northern Ontario in the dead of winter. It was cold, blizzarding and icy. They travelled 2,300 km during the coldest week of the year. And they did it in an electric vehicle (EV).

Destroying the cold weather myth.
 
That low level feed in tariff is quite usual here in the UK and many suppliers simply don't buy excess. :mad:

Our finding regarding PV and battery are that PV only reduced the amount of electricity we bought by around 50%. The limitations were:

  • The house uses around 5kWh per day to just keep ticking over. On average about half of this was covered by PV but in the winter we often generated close to zero.
  • Our oil-fired central heating adds around 400 watts to the demand when it is running. Unfortunately it runs most at night, in the winter, when the PV cannot provide energy.
  • Peak usage, for example cooking using the oven and a couple of rings on the hob, exceeded the PV's ability to generate AND
  • Our usage didn't necessarily align well with times when a lot of solar was available. For example we would use an electric dryer on cold wet days when there was little or no solar generation

Our investment in a battery will likely reduce our consumption by a further 25% and our expenditure to 10%-15% of what it used to be. Payback will likely be in 8-10 years and there aren't many investments out there with that kind of yield. The savings will come from storing PV generation for later use (like in the past two sunny days) and also by making use of cheap overnight electricity to charge the battery and then use that during the day to run the house when there is little or no solar generation. The case is made better by the UK's ridiculously high electricity costs (25p-30p per kWh).

the way it works by me is they install a meter socket that can roll back. build your array to overproduce when the sun is up to offset draw off the grid at night. no need for a battery if it’s just to cover the night
 

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