Solar panels and battery - any real world reccomendations?

So, should make any requirement to wait 2 months for the G99 irrelevant. You can get it installed and limited to G98 settings, whilst waiting for the G99 to be approved. Worst case scenario the DNO says no - and you just have to leave it being clipped until the local electrical infrastructure is up to it.
 
Bug One said:
So, should make any requirement to wait 2 months for the G99 irrelevant. You can get it installed and limited to G98 settings, whilst waiting for the G99 to be approved. Worst case scenario the DNO says no - and you just have to leave it being clipped until the local electrical infrastructure is up to it.
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To me its another one of the issues with solar in that the majority of the installers right now seem to want to nigh on decide for you, and to make life as easy for themselves as possible.

I suspect some installers would not want to have to deal with the drama of customers who purchased a 6kw inverter to be told they have to limit to 3.68

My approval came through within 4 weeks, but the installer was a) busy and b) there were shortages of equipment anyway, so my wait time was as much dictated by that as the G99 itself.
 
Ron-ski said:
Newer battery tech is coming, CATL have just launched a condensed battery with an energy density of 500Wh/kg.

To put that into perspective, my 14.5kWh battery weighs 80kg, the same weight as per above would be 40 kWh, almost three times as much. How green they are I've no idea, but I did read the other day that a company can now retrieve 95% of the lithium from old cells.

@Peteronthesouthcoast Not sure if you're talking about indivuals or the government. But its all well and good saying fit more panels, don't bother with batteries, but the average person has limited financial resources, and has to place those were they will be most beneficial to themselves, most of us also don't have room for hoards of panels. Although I do have some ideas for additional panels it probably would not be financially viable, but, if you want to donate so I can add more panels, then let me know ;)
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I don't think you will find I said do not bother with batteries. Both my car and house has them. I stand by what I said which is that panels are the top priority. I suspect I export more green energy than anyone else on this forum, and I am not free of the grid, so I do have a footprint. There is no plan-et B, and in my view we have been (both collectively and individually) the worst custodians of earth. When my children and grandchildren turn round to me and ask "Why did you do nothing?", the answer will be I am sorry but I tried.

There are going to be improvements all the time and we are desperate for them. We do not have a Tumble dryer and I disapprove of them really. We can and do have a garden where we dry our clothes. I accept that many people have to live in flats where they do not have this option. Years ago we all saw the white tubes hanging out of flat windows where a tumble dryer was venting moisture and allowing cold air in. Condensing dryers arrived which used less energy and did not need to vent outside. We now can buy heat pump tumble dryers which use about 30% of the energy of a condensing one. Some users are saying they get their money back from savings in less than 2 years. This is good news for the planet. Every step in the right direction is to be welcomed.

It is indefensible from a green viewpoint to have swathes of batteries we are unable to use and could support the grid. Because of this people like me have had to buy more batteries which we can use.

I accept that personally we are lucky to have a generous south facing roof. We deliberately chose a house with all principal rooms south facing and that was a no cost option. Limited financial resources always sounds great on the face of it. The cost of extra panels gives you a guaranteed (although unpredictable) output over time. Making a 10 year investment on the basis of curent prices from Octopus is a form of gambling. People with limited resources should be extra careful when gambling.
 
Peteronthesouthcoast said:
Making a 10 year investment on the basis of curent prices from Octopus is a form of gambling. People with limited resources should be extra careful when gambling.
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I disagree that batteries are a form of gambling here, stuff like Flux may not always exist, and you can't say for sure that really any current tariff will be the same in say 6 months or a year, but I think you can always find a way to leverage a battery to your advantage.

Even at a basic level, the battery allows you to run overnight off the grid if you size it right, which gaps between the daytime charge of solar.

Time of use tariffs with cheaper overnight import rates will probably be around for a while, so that is your battery helping out in Winter.

If the grid did net export/import then you could perhaps argue the battery isn't required (export 1 kWh one day, import 1 kWh on another at no cost), this would then just encourage more panels and more net exporting/importing.

Net import/export seems even less likely than the time of use options around batteries to me though.
 
I would go further than your time of use tariffs being around a while.
I predict they will become the norm, as part of helping to ensure that the grid can go as green as possible by encouraging people to use the grid when it has surplus and likewise penalise for when its running short of capacity.

Outside the *cough* gaming that some of us partook in, many people also diverted their usage from peak times for the reward.

I would suspect that given the right tariff a high percentage of them would be easy people to move to a TOU tariff. I bet some are even looking at agile right now.
Agile I think could potentially see a big uptick when the overall prices drop and we start to see very low / negative price in "peak off peak" (ie like 12 midnight to 4am)

I think it will become like a snowball turning into an avalanche. As tariffs come and people switch the price for normal will have to go up, since by default the people clinging to it will be those with peak peak usage.

Arguably the full benefit of batteries from an environmental aspect doesnt kick in yet. They have helped reduce the coal peaks, but wont really genuinely really have a high benefit until we start to get no fossil times where excess green energy is available that can be stored and used when it would have meant higher fossil usage.

Outside COVID energy is just going up, and I cannot see any hope / chance that within a 10 year window energy is going to become cheaper and more plentiful. I can see it being more volatile in supply and hence, hopefully, pricing.
 
We're planning to get solar in the next 1-2 years, but our boiler is on it's last legs. I think its 15-20 years old. If we need a new one before we start looking at a solar setup, are there any specifics that we should look for in a new boiler such as smart features or anything that would improve future connectivity with a solar setup?
 
If you are not looking at a heat pump or not. If you are going with gas then the only thing to consider is if you want/have a hot water cylinder or not. If you have a cylinder you can heat it with solar via an immersion heater.
 
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CryptKeeper said:
We're planning to get solar in the next 1-2 years, but our boiler is on it's last legs. I think its 15-20 years old. If we need a new one before we start looking at a solar setup, are there any specifics that we should look for in a new boiler such as smart features or anything that would improve future connectivity with a solar setup?
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A gas boiler? That will use the same amount of gas regardless.
 
b0rn2sk8 said:
If you are not looking at a heat pump or not. If you are going with gas then the only thing to consider is if you want/have a hot water cylinder or not. If you have a cylinder you can heat it with solar via an immersion heater.
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But it should be pointed out that tariffs like Flux make solar immersion heaters redundant.
 
Scottm said:
But it should be pointed out that tariffs like Flux make solar immersion heaters redundant.
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If flux suits you that is. Its not for everyone.
It kind of relies on having an excess of generation, plus good enough controls to make it work.
For example my Solax inverter cannot be setup to play nicely, and on max discharge I can empty my batteries from full in under two hours so would need to be careful to not empty them during the prime export window else I could end up buying back the very expensive units
I can almost fill my batteries on my tariff for the price of 1kWh peak flux import prices!

Its not for everyone, and a lot will depend on Octopus gatekeeping the switches to and from smart tariffs in future.
I believe strictly speaking your not supposed to be able to switch from a smart to another smart without a 30 day cooldown.
IF you can flux and switch back to a nicer tariff for the winter its far better than if that is going to be a problem.

b0rn2sk8 said:
That’s true and the ROI is very long on a solar diverter in any case.
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Yeah indeed, realistically until recently I was only saving a couple of pence per kwh that went to the immersion instead of the gas boiler to heat water.
But today my gas price has dropped to 4.43p so I would say its probably a penny now. (I assume 85% efficiency for water heating for boiler and inefficiency of sending to tank)

I would still have had it fitted however. Only the cost of the unit whilst having solar fitted and I think in 6 months the landscape has changed twice in regards whats the most optimum strategy in regards my solar charging and use.
I cannot imagine we have seen end state yet!
It would have cost me over a third to get a decent time controller for my immersion rather than a simple switch.
 
A diverter is only around £300 - you'd save that fairly quickly instead of using gas to heat your water, or am I missing something? I guess you could just programme the heater to come on when there's excess solar - but it just does it automatically so it takes that faff away.

We still have gas and will likely have gas for a while as ASHP still aren't efficient enough to be sensible IMO. When we do our extension one of the things we will have is underfloor heating and a ASHP is very efficient for that, but we may just have the ASHP for the extension and leave the rest of the house on gas. Haven't decided yet.
 
Freefaller said:
A diverter is only around £300 - you'd save that fairly quickly instead of using gas to heat your water, or am I missing something? I guess you could just programme the heater to come on when there's excess solar - but it just does it automatically so it takes that faff away.

We still have gas and will likely have gas for a while as ASHP still aren't efficient enough to be sensible IMO. When we do our extension one of the things we will have is underfloor heating and a ASHP is very efficient for that, but we may just have the ASHP for the extension and leave the rest of the house on gas. Haven't decided yet.
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Yeah but it all depends on the price of gas, the price of elec export.
Which is why its a continually moving beast.

If your paying 12p for gas and 4p export on elec its saving probs nigh on 10p per kWh (assuming gas is around 85-90%) efficient

Right now my gas is more like 5p though so the margin is low.
I am just about to turn the boiler basically off however for the summer I think.

The diverter will also allow (well mine does) you to set normal heating as well. I was about to start playign with using the 7.5p go tariff to heat my water when I switched my gas to the tracker and basically at the start they were nigh on the same cost.

I haven't included the cost of running the pump but I don't think its massive for a shortish burst to heat the water. Seems to be about 150w or so from what I can tell.
 
HungryHippos said:
I disagree that batteries are a form of gambling here, stuff like Flux may not always exist, and you can't say for sure that really any current tariff will be the same in say 6 months or a year, but I think you can always find a way to leverage a battery to your advantage.

Even at a basic level, the battery allows you to run overnight off the grid if you size it right, which gaps between the daytime charge of solar.

Time of use tariffs with cheaper overnight import rates will probably be around for a while, so that is your battery helping out in Winter.

If the grid did net export/import then you could perhaps argue the battery isn't required (export 1 kWh one day, import 1 kWh on another at no cost), this would then just encourage more panels and more net exporting/importing.

Net import/export seems even less likely than the time of use options around batteries to me though.
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The gamble is the difference in price between cheap and expensive units. The larger the difference the more that batteries become a good choice.

We have to store electricity and double dams are the most obvious answer. After the capital cost of doing this has been accounted for, 0.85kw will come back from 1kw used in times of surplus. Batteries connected to solar systems are such a small percentage as to be insignificant. They cannot form part of the solution. Car batteries are an entirely different matter. There are apparently 660,000 electric cars. Let us assume they will all have 4 x 7kw available during the peak time of 1600-2000. 28 x 660,000 gives us 18.5 million kwh. There are 26 million homes in the UK. Less than 2% have solar. This gives us a max of 500,000 homes with solar. Battery back up might be as high as 50% (guessing here). If all of those can afford to give 4kw each we have 1 million kw from houses. Electric car ownership is growing a lot faster than batteries in houses.

In 2018 we were camping on the banks of the Rhine close to Strasbourgh. We cycled past a Hydro scheme on a tributary of the Rhine. There was a small building with a drop in the water of only 2-3 metres. There did not appear to be any water gushing out. There was a display showing the output of around 11,000 kw. A notice explained that many more were planned and at the moment they were working 24 hours a day. Longer term, when new turbines came on stream, they were planning on using them to boost electricity production at peak times. There was a finite amount of water they had available, so this would get the most out of it. We have a lot of rivers and could do this.

There are many different ways of tackling the problem of matching supply and demand. We have never had such a big gap between TOU tariffs. Does that mean the gap will shrink and make batteries less attractive? I think it might.
 
Peteronthesouthcoast said:
The gamble is the difference in price between cheap and expensive units. The larger the difference the more that batteries become a good choice.
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This is still only part of the picture. This means more for off-season Winter usage.

Electric prices in general matter more. Solar and battery only really makes long term sense from a fiscal PoV if you are saving on the average unit price paid.

My opinion on this is that we will likely have elevated electric prices for the next few years.

Beyond all of this, this is something you can do. I can't install or run a hydroelectric power plant at my property, but I can add solar + battery tech, and it helps save me money in a self-custodial system.

I'd estimate my 1st year of savings is likely to be ballpark £1 - £1.5K thanks to this tech combo. Given the cost was £8.5K, this would leave me with a £7K deficit or so after a year, which is fairly good going.
 
Peteronthesouthcoast said:
Car batteries are an entirely different matter. There are apparently 660,000 electric cars. Let us assume they will all have 4 x 7kw available during the peak time of 1600-2000. 28 x 660,000 gives us 18.5 million kwh. There are 26 million homes in the UK. Less than 2% have solar. This gives us a max of 500,000 homes with solar. Battery back up might be as high as 50% (guessing here). If all of those can afford to give 4kw each we have 1 million kw from houses. Electric car ownership is growing a lot faster than batteries in houses.
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I'm really failing to see what you are saying here. Do you really think all those cars are parked in suitable locations, and have enough charge to discharge 28 kWh between 1600 - 2000? Cars are for driving, not sitting on drives (if you have one), my car is out all day when I'm at work, so no charging from solar if it was electric.

Yes I do agree we need to be more green.
 
Don't think I can think of a single solar install I know of recently that didn't include batteries of some description.
They make a lot of sense for just about every individuals use case IMO.

All the off gridders use them, if anyone is going to be after the most reliable use case its them.

I think V2G may be a massive over reach. Whilst I am sure some will be happy to do this, those on company lease schemes maybe I think the added charge / discharge is likely at some point to be monitored by and restricted by the manufacturers.
They have no reason at all to basically provide you a house battery that potentially degrades components within the warranty period. None at all.
Suspect it would become a fair usage thing, "enabled" for occasional emergency useage.
Just my gut feel.
 
Mercenary Keyboard Warrior said:
Don't think I can think of a single solar install I know of recently that didn't include batteries of some description.
They make a lot of sense for just about every individuals use case IMO.

All the off gridders use them, if anyone is going to be after the most reliable use case its them.

I think V2G may be a massive over reach. Whilst I am sure some will be happy to do this, those on company lease schemes maybe I think the added charge / discharge is likely at some point to be monitored by and restricted by the manufacturers.
They have no reason at all to basically provide you a house battery that potentially degrades components within the warranty period. None at all.
Suspect it would become a fair usage thing, "enabled" for occasional emergency useage.
Just my gut feel.
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I agree V2G may be a hard sell unless government incentivised it... but V2H i absolutely think will be a goer........ the battery warranty may be an issue... but if you are talking just 10% of the battery allowed per day for instance, the reality is that is only one full charge every 10 days extra and that may not be such a big deal, esp with battery tech improving all the time.
 
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