PV solar panels and battery storage in the UK

Last updated on January 5th, 2018 at 09:26 am

The wrong people always teach us the right lessons in life, and that is especially true when it comes to those who are currently selling the new battery storage and PV solar panels.

Tomorrow's world with PV solar panels, battery storage and electric vehicle charging.

Tomorrow’s world with PV solar panels, battery storage and electric vehicle charging.

This week, the first Tesla Powerwall battery storage system was installed into the lives of a Welsh family.

Unfortunately, in the same week, we’ve learned that other solar companies offer and are overcharging for battery storage systems against wildly exaggerated claims.

These types of sales-based companies are identified by minimum technical knowledge and using high-pressure sales tactics. These cold-calling types are only a minority, but who are spoiling for the majority of decent installers in the solar industry.

The reality of battery storage systems working alongside PV solar panels is that they are a definite new direction for the solar industry, but realistically not for everyone.

Many ethically-minded installers are divided at this early stage as to its benefits, especially as there are so many variables. The ‘one-size fits all’ approach is no longer sensible when selling photovoltaic with battery storage. I suggest that’s it depends on the final installed cost as to the viability for most people.

Here’s what to look out for:

One trusted installer I know has just been to see a couple that was quoted £11,500 for a 3 kW system with battery storage and voltage optimiser by a national company.

The sales rep told them they would be off-grid for most of the year and their total savings would be over £1,000 per year, despite the fact they’re existing bill, is only £650.

This claims can be many thousands of pounds overpriced, and claims made are just wrong. Similar situations will be happening each day throughout the country as these types of companies adapt to recent feed-in tariff changes.

The single most common aspect of getting a good quality solar panel system installed by an ethical installer at a reasonable price, so that you can genuinely benefit financially is research, research, research.

The simple truth is that hard-sell companies thrive off ignorance!

“Our solar panels are better than their solar panels” and “sign up today for a special discount” is a clear signal to turn your back and find a better installer.

Discounts and special offers are designed to whip you up into a frenzy of excitement, so you sign-up that day. If you don’t and research first, then they know they have lost you.

The fact the FIT incentive scheme attracted sharks into the industry has not done the industry any favours. However, solar panels are genuinely a beneficial technology and great at what they do; it’s just a shame that the con men are still out there today.

Ultimately, solar panels are a great way of reducing our dependence on an ailing and increasingly costly energy network. You can benefit financially long-term, but only if you get a simple system at the right price.

The truth of battery storage – facts and figures

A big thank you to Andy at Lincolnshire Solar for this breakdown of the reality of battery storage systems running alongside PV solar panels.

A Typical house using the national average of 3800 kWh per year and solar PV system generating 3500 kWh per year.

Price of electricity per kWh is £0.12 pence.

The Energy Saving Trust quotes an average saving of £125.00 per year for a typical home; they also quote £0.145 pence per kWh.

£125.00 divided by £0.145 = 862 kWh used in the home from the generated solar PV system or a saving of 23% of the 3,800 kWh.

So what else can you save by installing a battery storage?

Look at it this way, if you use 3,800 kWh per year, you use on average 10.41 kWh per day, so it’s only possible to save 10.41 kWh per day.

From data downloaded from my customers SMA inverters, I have come to the following conclusions.

Real PV facts, real figures

3 KW solar PV generating on south facing roof 3000 kWh per year.

The unit price of electric per kW, £0.13 pence.

Ordinary PV savings without Battery storage according to the Energy saving trust (EST) is £125.00.

The EST quote £0.145 price per kW so £125 divided by £0.145 is 862 kWh per year.

Battery Storage savings over 300 days @ 5KW (size of battery bank) 1500 kWh @ £0.13p = £195.00.

FIT payment if available 3000 kWh @ 4.3 p = £129.00.

Export payments 3000/2 x 4.86p = £72.90.

The total savings for year 1 = £125.00 + £195.00 + £129.00 + £72.90 = £521.00.

Battery lifespan is ten years or 3,000 cycles.

Important technical details to check

Solar PV systems with battery storage may not be eligible for the FIT’s payments if installed before the generation meter.

One benefit of the Solax inverter charger is in the event of a power cut the inverter can power the home up to a maximum load of 2kW, a manual changeover switch is required to isolate the incoming supply, and an external earth rod is necessary to earth the property.

Geographical location

It is important to point out that PV solar panels installed in different locations will give different output figures. However, as these numbers produced in Lincolnshire and this is a central location within the UK, I would use them as an average with more significant figures occurring the more southerly your location and lesser data when your situation is more northerly.


There are brilliant battery storage systems on the UK market that are tried and tested around the world. PV solar panels working alongside battery storage devices and even EV charging are an option to consider in addition to the current incentives for solar panels. A good solar installer will be able to advise you on both types of system.

Yes, there are sharks in our industry as with any other, but clear facts will always trump ‘bullshit’ sales when the time is taken to research your options correctly. Remember sharks feed off ignorance!

Yes, solar PV and battery storage systems are on the rise, and it will remain a viable option for many when bought at the right price from a trusted MCS installer.

Being a solar pioneer isn’t easy, but nothing worth doing ever is!


"Feel the pride."
March 2, 2016
Founder of Power My Home.

  • Denise Van Velzen

    We have been victims of a silver tongued salesman,after contacting their head office/salesman and area manager, we have reached a stalemate.
    Does anyone know who we can go to for help please, RECC/REAL will not cover us as we bought solar panels separately (2014), tried C.A but get put on hold for so long, do not want to go with section 75 to loan company,as I feel the solar battery firm are the one’s we are disputing, not loan company.
    Please can anyone advise

  • Alternatively, if you have a hot water cylinder then storing your excess power in the
    form of hot water via a power diverted is a much more cost effective
    method right now. These devices supplied and installed are around £500.
    Ten percent of the cost of batteries.