2 EVs, Solar System Suggestions?

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well there we go, solar installers are flat out, very long protracted dates for instal, but not what you anticipated......

Took me 2 weeks from enquiring to having scaffolding put up at our house. But, yes, like I said I know there is currently high demand from solar installers, due to there not been infinite amount of them. But that wasn't really the point I was trying to make, I assume your making that comment into an argument, just because.

As before, whatever, think what you like I KNOIW what the reality is.

Fair enough, don't bother trying to explain the errors in the calculations I've shown, that even uses your numbers. As long as your reality makes you feel good that's the main. The great thing, other people reading this thread, can look at your ROI calc, and look at mine and make there own minds up.

mining Chia.

Thanks for that 👍 , that does look more promising, I'm in IT, old HD's are something I'm not short off. I think it was BitCoin / Ethereum calcs that didn't make any sense, but Chia sounds way better.
 
Thanks for all the input. I understand completely the sense in buying a battery, I just don't have the budget at the moment to fit one in with a decent panel configuration, that then leaves the issue of getting a poor panel count with small inverter and small battery, which then gets wiped out charging cars, or a decent panel setup initially that will cover the cars requirements and add a battery later funds permitting.
 
We all have to cut our cloth accordingly :)
Better to do one part of the job well and do the rest later when circumstances permit than do a half-baked job and rue the effect for the next 10yrs

The battery only option might be worth a look, cheap overnight elec all year round on a suitable EV tariff, depends what your biggest elec use is from.
e.g. https://www.bimblesolar.com/ongrid/hybrid-inverter-bundle-storage

If I've got my head around it correctly you can charge your batteries and EVs overnight on cheaper elec and use the stored energy in daytime for the house?

you could always just put a couple of cheap panels on shed roof to get 0%vat ?

enjoy deciding!
 
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If I've got my head around it correctly you can charge your batteries and EVs overnight on cheaper elec and use the stored energy in daytime for the house?
That’s exactly right and what I do. All of my electricity is at 7.5p or free if the weather is good. Batteries and an inverter make sound economic sense if you have a good off peak tariff.
 
I love having Solar + Battery, but because of this 7.5p off peak, if I had a choice of only one it would be battery.

Also if budget is an issue, I would say it's the Solar part that is expensive bit due to installation costs. etc.

Like mentioned if you get a big enough battery for you use, your getting all your electricity at 7.5p.
 
All this is based on Octopus offering 8p/kw though? At a certain point Octopus are going to decide enough people have electric cars to bring the price up?
 
All this is based on Octopus offering 8p/kw though? At a certain point Octopus are going to decide enough people have electric cars to bring the price up?
Whilst that 'could' be true, I doubt it, they have just reduced their off peak tariff on Intelligent from 10p to 7.5p, why would they do this if on the horizon theyre going to increase prices? I have been with Octopus 5 years and they have consistently been the cheapest off peak by quite a margin.
 
Peak / Off Peak tariffs are not new, been around for as long as I can remember. Was known as Economy 7. So this off peak pricing is not just some modern fad.

But I do see your logic, if everyone had electric cars charging at night, would that mean it's now peak, and will therefore increase prices.

The thing is electric demand is never flat, and will likely never be flat. It's not always windy, & not always sunny, turbines take time to come online / offline etc. etc. With a battery you would be in a position to take advantage even if off peak times changed. Octopus even have a tariff were you can purchase plunge priced electric, with this people have even been known to get paid for taking electricity off the grid. It's called Agile Octopus, but because of the current energy crisis might be one to avoid for now, but when things settle again might be worth a look.
 
Study octopus flux. Your cheap rate for three hours at night is about 20p but your export is 24p approx. So when you are exporting you are gaining that night rate. I use a gas kettle because the solar is worth more to me exported than it is self-consumed.

One thing though - if you propose to charge two evs simultaneous and operate for example night time time-delayed dishwasher and washing machine, check your household fuse. If only 60w you might need to upgrade it. 6700w level 2 charger timestwo = 13400w plus a couple of other appliances doing say 2400w each equals 18200 w/240 is 76amp! 16 more than a lot of household fuses.
 
Study octopus flux. Your cheap rate for three hours at night is about 20p but your export is 24p approx. So when you are exporting you are gaining that night rate.
Octopus intelligent is 7.5p for 6 hrs at night, forget export , use all of it yourself which should be easy with a battery, 2 x EV and an electric kettle!

I use a gas kettle because the solar is worth more to me exported than it is self-consumed.
About 0.183 kWh of energy to boil 1 litre of water in a kettle so with your 24p export rate that would cost you 4.4p, I dont think it would figure highly in choosing a system or export tariff for that matter.

One thing though - if you propose to charge two evs simultaneous and operate for example night time time-delayed dishwasher and washing machine, check your household fuse. If only 60w you might need to upgrade it. 6700w level 2 charger timestwo = 13400w plus a couple of other appliances doing say 2400w each equals 18200 w/240 is 76amp! 16 more than a lot of household fuses.
Yep, most supplies can be uprated to 100amp if it's a not on a looped feed.
 
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