Solar panels / batteries / cheaper energy at night

I've just had a thought. If you can have solar panels on your roof with a battery to generate energy during the day that is then stored to use whenever you want it then is there anything you can buy to do the opposite?

When the energy is cheaper at night, flip a switch which charges a battery just like the solar panels do, then use that stored energy during the day.

Surely that exists?

 

It absolutely does.
Many people are now charging a battery up at Eco7/Eco 10/off peak tariffs and then using the electric the next day.

 

Even without Solar Panels.

 

Ay idea if it actually makes much if any money? I'm guessing the batteries etc aren't cheap

 

Guy in the Mirror, claiming he charges his car on cheap tariff and sells back to grid on dearer tariff and reduced his monthly bill to £7.50 a month.

 

But he’d only sell back on whatever he can export after what’s he’s used of what he’s produced.

We have a I-boost which generates our hot water when we start to export, since 1st out gas boiler has been on once (that didn’t go down too well either ) so as far as a monetary saving goes we should have over 4 months of the year where we generate all our hot water. If anyone can afford solar it’s definitely a worthwhile investment

 

The way to make it pay is to know how much electric you use in a day and size your battery to cover it. If you use 8kWh per day, you need an 8kWh battery. That way if you’re paying 28p/kW during the day and 7p/kW off peak you’re cutting your bill by 75%.
I reckon you’re in for about £1000/kWh when you include the cost of the battery and inverter, but with the rate electric is going off you’d have covered the cost of the battery etc within 8 years based on a £120/month electric bill as of now, and obviously if the price keeps rising you’ll have saved the value even sooner.
It does work better with solar too, but if you have an immersion heater you can run from the battery or electric heating you might even save more.

 

My 200Ah batteries were close to €1000 each. Works out to about 2.4kwh per battery.

 

Was that recently? They have come down in price quite a lot in the last couple of years.

 

Apologies for being stupid, but how does the electricity company know if you use your electricity during the day or at night? My electricity meter (and every electricity meter I have ever had at well over 20 addresses) has a single row of numbers that someone is supposed to read every quarter, but don't, which means I have to read it. And not one of them has a day/night feature on it.

 

If you have a smart meter it knows. If you don’t have a smart meter but have economy 7 or economy 10 you end up with two meters and two fuse boards.

 

i hire them through work quite often. £450 a week to hire.

 

Seems weird electricity is more expensive during the day. I'm not in during the day, I'm at work, and if I am in, I don't use the lights as sun's out.

 

It’s because the generators run all day, but the e majority of the demand is at certain times.
The grid and electric providers want you to use it equally over 24 hours to smooth the amount they need to generate.
Traditionally the eco7 was used to run electric storage heaters/immersion heaters, but now there is a battery option it’s being used in different ways.

 

I don't understand why all new builds don't have a legal requirement for solar panels, plus whatever else can be fitted. I know we don't get much sun, but surely it's got to be best all round from a cost/environmental perspective.

 

Because greedy developers can't make obscene profits if they have to fit stuff like that. People can only aford to pay so much, and if the cost of the build takes up most of the selling price, developers won't build.

 

The cost would be passed on to the purchaser anyway. All buildings should have to do a calculation as to their expected electrical demand and a suitable and sufficient renewable system should be installed at build.

 

End of last year around November. They are LiFePO4. All the solar gear is coming down in price all the time but when you are at the stage where you need to do an install you shop around and buy...
I have 600w of panels, MPPT Controller, 400Ah of batteries, invertor, monitor etc

 

Yes, but developers could reduce their profit margins to assist this kind of transformstion - but they won't.

 

They absolutely could, but then they’d have to manage new build sites better. I worked on one as an assistant site manager for two weeks and saw 3 brand new kitchens thrown in the skip because they’d ordered the wrong ones.