Electric car charging

DrEskimo

Robin9 wrote: »

A really attractive Smart tariff might well be a good option as well - an hour here, an hour there ??

Yea I like the look of Octopus' Agile tariff paired with a smart cable (so it works with your existing charge socket) that allows you to periodically charge when electricity is cheapest.

You just set the charge you want by the time you want it, and the cable will pick the optimal times to do charge to save you the most money.

https://www.fleetpoint.org/electric-vehicles-2/tech-innovator-octopus-energy-partners-with-ohme/

AdrianC

...a £400 cable...?

Their £300 "annual saving" is based on the difference between the cable on their cheapest tariff, and "four of the big six"'s standard variable rates (bet they didn't pick the cheapest four). Rigged, much? I'd love to see a straight comparison - the same tariff, with and without the smart cable...

Any bets on the RoI being massively long?

DrEskimo

AdrianC wrote: »

...a £400 cable...?

Their £300 "annual saving" is based on the difference between the cable on their cheapest tariff, and "four of the big six"'s standard variable rates (bet they didn't pick the cheapest four). Rigged, much? I'd love to see a straight comparison - the same tariff, with and without the smart cable...

Any bets on the RoI being massively long?

Good point...

I guess it becomes less of a cost issue if you are looking to buy a cable anyway, but most EV's come with one!

I'll see if I can dig up the actual figures for the £300 claim and see how it compares to my current tariff, which is just their 12m fixed duel fuel.

silverwhistle

As a PV owner my import is <1100 kWh a year, so I can safely ignore the "£300 savings" stories!


It'll be an interesting calculation to select an appropriate tariff when an EV does finally arrive for me.. Still, that will be a few years yet, my car is only 9 years old.

DrEskimo

"* Based on a vehicle doing 10,000 miles per annum, with average efficiency of 3.4 miles/kWh. Savings were calculated based on a comparison of Octopus Agile energy prices and Standard Variable Tariff prices from four of the Big Six between May 2017 and May 2018. Assumes all charging is conducted in low-price periods."

https://octopus.energy/ohme/

It's very difficult to find an estimate for the average SVT in terms of £/kWh, but I imagine it's in the region of £0.17-£0.20. Given they randomly pick 4 of the 6, I suspect it could even be a bit higher.

10,000 miles at an average of 3.5mi/kWh would mean 2,941.18 kWh of electricity consumed, and all charging is assumed to occur off-peak.

If you could fit that into the 4hours they offer with their GO tariff, which has a rate of £0.05 between 00:30-04:30, then you would see similar savings without the need for a £400 cable...

https://octopus.energy/go/

almillar

I would expect another phase has been brought into the property. My uncle has 3 phase in his private house so has 450V available.

3 phase is very rare in houses, AFAIK.

Best you can do usually is 7kW at home ( I got this 'free' with my Renault Zoe). That's 240v, 32A, single phase. That means you need a 100A fuse for your home, generally, and some have 60A fuses, I think, and need to be upgraded - which the utility provider needs to do.
Yes, it's a bit of a bureaucratic mess, but it only happens once.

Would make the batteries last longer, too.

What do we mean by slow charger?. 7kW is slow, relative to 50kW rapid charging. Even then, car companies are getting more relaxed about rapid charging as they get data back saying it's not as harmful as they feared, and as they get better at battery (and temperature) management. 3 pin would be 2.4kW, 240v, 10A. No need to go that slow unless you can't get a charger installed, or want to sip on solar energy.

So can someone explain the options and costs for setting up for home from scratch from basic to best assuming you don't have a 3 phase.

No charger. 3 pin 'granny' cable. 2.4kw. Slow, slow charger, 3.6kW. Slow charger, 7kW. That's your options before you go 3 phase.

As has been pointed out though, not a lot of cars go faster than that on AC - Zoe can do up to 22kW, or even 43kW, some i3 can do 11kw, some Tesla too I think. But 7kW, for 8 hours, would give you 56kWh of electrical storage. So that would be more than a full charge for a 40kWh Zoe, which can travel 180 odd miles. Let's say you can get 200 ish miles, overnight, at home. EVERY day. If that's not enough for your, maybe consider 3 phase, or diesel...

AdrianC

DrEskimo wrote: »

If you could fit that into the 4hours they offer with their GO tariff, which has a rate of £0.05 between 00:30-04:30, then you would see similar savings without the need for a £400 cable...

Or, to put it another way, the cable itself saves three quarters of nowt.

DrEskimo

AdrianC wrote: »

Or, to put it another way, the cable itself saves three quarters of nowt.

Indeed...

In fact it's even hard to justify why you would opt for their AGILE tariff sans the expensive cable over their GO tariff.....

Hope I am able to benefit from it when/if I move to a house with home charging!

Jackmydad

Robin9 wrote: »

I was Distribution Company design engineers many years ago and we talked in terms of After Diversity Maximum Demand - this said that although you had many appliances you only used a few at a time; your neighbours had the same but used them at different times; some neighbours would be on holiday; some houses empty etc. Typically when gas was used for heating we designed our underground cables to 1.6kw to ensure every one had a statutory voltage.

I see an issue of old estates with lots of electric cars with say 7kw charging points all being used at night creating problems for the distribution companies.

As Robin says, there will be problems if everyone goes over to EVs.
It hasn't been thought through, and the job of changing thousands of miles of cable, and thousands of sub stations to take the higher loads is going to be extremely expensive.
Where's that money going to come from?
And that's before you look at generation capacity.

Ectophile

di-di-di-dah-di-dah wrote: »

You wouldn't be able to charge at home because I'm pretty sure you can't just lie high voltage electric cable across the path.

Since this forum excels in pedantry, if it plugs into a wall socket, it will be low voltage. It's only high voltage if it's over 1000V.