Anyone know anything about Solar PV and Batteries

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With the soaring price of grid electricity was thinking about maybe getting Solar PV and battery setup at home. Worth it or waste of money? Confused by the numbers though. Let's say I got a 6kW solar PV array and 8.2kW battery storage. Could this be used to charge up the old MG5, if so how much? Would that storage battery only be able to add approx. 32 miles to the MG before it was depleted? Like I said I know nothing about this sort of stuff, hell I only got my EV a few weeks ago. Anyone on here got experience, good or bad, with such a setup. I've seen a Youtube of EV man saying how great his battery setup is but ... is it really?
 
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The battery storage is primarily designed to run the house after dark with the battery being charged during the day. I ruled that part out because we plan what we are doing specifically about the weather so sunny days are for batch cooking, washing and tumbling and charging the car if at home.

The net result is not much power for the batteries on most days. I would love to expand my 3.6kW PV array but we installed when FIT was still being paid, an upgrade is classed as a new install so I would lose the payments.
 
Ah, so the battery is powering the house once the sun' gone down, so can't also be used to charge the car. So is it a choice between charging the battery for the house, or charging the battery for the car? Sorry if that's a dumb question 😜
 
No, the battery generates A/C for the house and the car is connected to the house so it would be charged from the battery.

But do the math. Even if fully charged the 8.2kW battery is not going to do much for the car's 50kW+ battery and if you even did that then the house is going to pull power from the grid for it's needs. You could possibly set a timer for the car to drain the battery after you have gone to bed but how much would be left after an evenings TV, computer, lights, central heating pumps and the hair dryer?

At an average of 14.40p per kWh if you caned an 8.2kW every night how long would it take to recoup the outlay and treating the battery like that is not good for longevity.

Solutions that generate electricity actually makes the money as it works so solar PV makes sense. Some EV cars can be used as a power source but even those solutions are not cheap.
 
Battery and a time of use tariff. Charge battery and car midnight to 4am at 5p/kwh, use battery during the day instead of grid at 32p/kWh. Someone posted a video in the general EV channel, you can pay off an 8kw battery in about 3-4 years.
 
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But if you are using the battery during the day then that is the same as using the panels, the best the battery will do is make todays dull day into yesterdays sunny one, only if you stopped them being used overnight.
 
I'm planning to install some solar panels (4kw+) soon. I used to live on a barge with 2.5kw panels, and I was able to charge electric Kangoo 3-4 hours a day during the season. I bought variable current charger and I was charging at 6 amps (around 5 miles per hour)
 
I tentatively looked at Emilio battery but the price just wasn't worth it in the several thousands. Our PV is only 1.8kwp from 2010 but we're on the maximum fit tariff. I think the battery would only be decent for storing extra power during a low overnight tariff and then using it outside of that period. Solar PV generates diddlysquat compared to a 61kw car.
 
I’m looking at battery storage without solar. Key is having a tariff like octopus go where you can access the cheap rate of 7.5p Over a 4hr night period. It’s then about charging battery during this time whilst also moving as much to that cheap rate as possible. For example, set dishwasher, washer etc to start in that cheap zone. Then in day use the battery to reduce need for the higher rate energy, which you will still need.
My calculations show it would pay cost off in around 4 years.
 
PonteMG5 said:
I’m looking at battery storage without solar. Key is having a tariff like octopus go where you can access the cheap rate of 7.5p Over a 4hr night period. It’s then about charging battery during this time whilst also moving as much to that cheap rate as possible. For example, set dishwasher, washer etc to start in that cheap zone. Then in day use the battery to reduce need for the higher rate energy, which you will still need.
My calculations show it would pay cost off in around 4 years.
Click to expand...
Max out the main fuse!
 
PonteMG5 said:
I’m looking at battery storage without solar. Key is having a tariff like octopus go where you can access the cheap rate of 7.5p Over a 4hr night period. It’s then about charging battery during this time whilst also moving as much to that cheap rate as possible. For example, set dishwasher, washer etc to start in that cheap zone. Then in day use the battery to reduce need for the higher rate energy, which you will still need.
My calculations show it would pay cost off in around 4 years.
Click to expand...
This is what I meant above. I'm looking at the same. It's about using the battery to shift your usage to the cheaper rate. Yes there are conversion losses and longevity issues if you're min/maxing the battery every day, but if it pays itself off in 1/3 of the time of PV you can reinvest for enough packs that you're able to replace or have enough capacity for the 20/80 optimal cycle range or newer tech. If you have a 100amp main fuse you can easily charge a battery and an EV in a 4 hour window, possibly 2 EVs if your daily use is below 30% range capacity with some smart load balancing.
 
Yes, I have an 18kWh battery which is fully charged at 5p rate between 12.30am - 4.30am. Precious little solar pv produced during these cloudy days (5.92 kW) but the battery will run the house off-grid until 10pm most days, sometimes completely off grid if there's a small back up of solar. I can also charge the car as well during the night time rate at the same time as the battery when I'm drawing 15kWp of the grid.
 
Is it possible to just have a battery and no solar just to shift the off peak tariff and what size and price would that be
 
Note that I was reading an article the other day (wish I could find it) that a lot of energy providers are looking at offering cheap overnight tariffs locked to EVs etc. going forward whereby they will only pay the cheap rate for what is consumed by the EV charger (via an app), rather than whole household useage.

I guess the biggest issue is that currently the night rate is cheap because electricity consumption is a lot lower than the day time. However if more people get EVs and charge overnight, plus shift their high power appliances and home batteries to be used/charged overnight, demand on the grid will increase and push the prices up, especially as no solar is produced in the night.

There is a graph somewhere that shows night time energy usage has been steadily rising for a few years now so it won't be long.

What you've got to work out is can you get the pay back for your setup before those benefits are lost?

For my location, roof direction, usage etc. it worked out that it would take me 11 years to get my money back. By then I'd need to replace the Inverter (they don't last that long), which would take another few years to recoup. Batteries actually made the situation worse for me, even though most of my non EV usage is at night because we're at work during the day.

Lots of people have had success from it mind you, but I do think the overnight bubble will burst soon.
 
I have a
3.5kw solar
13kw tesla powerwall 2 battery
Zappy ev charger
OCTOPUS go tariff
Mg zs ev car

This time of year I charge the
Tesla for 2 hours at cheap rate.
The car 14kw about 2 hours cheap rate. And all works great.

In the summer as we have the zappy
The solar fills the Tesla and any extra solar is diverted to the zappy and charges the car. The car then takes the ballance os 14kw daily charge from gride or battery at cheap rate at night.

All works great for me.

It's all about daily needs and timings

Take your time and do the maths and research.
Good luck
 
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Ozzie1989 said:
Note that I was reading an article the other day (wish I could find it) that a lot of energy providers are looking at offering cheap overnight tariffs locked to EVs etc. going forward whereby they will only pay the cheap rate for what is consumed by the EV charger (via an app), rather than whole household useage.

I guess the biggest issue is that currently the night rate is cheap because electricity consumption is a lot lower than the day time. However if more people get EVs and charge overnight, plus shift their high power appliances and home batteries to be used/charged overnight, demand on the grid will increase and push the prices up, especially as no solar is produced in the night.

There is a graph somewhere that shows night time energy usage has been steadily rising for a few years now so it won't be long.

What you've got to work out is can you get the pay back for your setup before those benefits are lost?

For my location, roof direction, usage etc. it worked out that it would take me 11 years to get my money back. By then I'd need to replace the Inverter (they don't last that long), which would take another few years to recoup. Batteries actually made the situation worse for me, even though most of my non EV usage is at night because we're at work during the day.

Lots of people have had success from it mind you, but I do think the overnight bubble will burst soon.
Click to expand...
Will be interesting to see if/when/how they lock it to the ev chargers and that could well change the game for battery storage. However, even with additional demand of EVs there is a long way to go before the grid would be balanced for night time use, so see that as less of a threat.

The whole model of savings is as you say, how that cheap night rate is accessed and remains cheap.
 
Same here as we are having an air source heat pump installed in March and it would be beneficial to time shift some of our electricity usage.

However, I think it only works financially if the off peak tariff continues. Can we be certain that this is the case? The CEO of Octopus emailed an update on the energy market recently and the subtext was nothing is certain but uncertainty.
 
I already had solar Thermal & Biomass when I bought my 1st EV in 2016.

The EV created the biggest savings for me.

Next I added a 6.75 kw solar array, limited to the 6kw peak allowed by the DNO.

The solar PV with FiT & Export, plus usage gave me a 5% return.
A Zappi was installed at the same time and increased my return to 8.5%
I then added Eddi and increased my return to 10.5%

A battery would have reduced my return, alone it only gives me 1-2% return with what I have done and even with the best buying / selling of power only 3-4% return.

If you have solar, use that power to charge your car, heat up water, run appliances etc.

A battery works best when you are out all day & cannot use power via diverters, timed appliance runs etc.

I cannot get a return from a battery within it's lifespan.
 
Even with solar and single rate tariff I couldn't get a battery system to pay for itself.

I would love to expand the PV but that knocks out the FiT rate I am getting.
 
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