Frequently Asked Questions

Everything you wanted to know about solar.

Honest answers to the questions we get asked most often. If yours isn’t covered here, just give us a call — we’re always happy to talk.

General Cost & Savings Installation Battery & Tariffs Warranty & Aftercare Commercial

General

The basics

Do solar panels work in the UK climate?

Yes. Solar panels generate electricity from daylight, not just direct sunshine. They produce power even on cloudy and overcast days — just at a reduced rate. UK homes typically generate 850–1,000 kWh per kW of installed solar per year, which is more than enough to deliver significant bill savings across the North West and the rest of the country.

Is my roof suitable for solar panels?

Most pitched and flat roofs are suitable. South-facing roofs perform best, but east and west orientations still produce strong yields (typically around 80% of a south-facing equivalent). We assess shading, pitch, condition and orientation during your free home survey. If your roof isn’t suitable we’ll tell you straight — we won’t install where it doesn’t make sense.

Do I need planning permission to install solar panels?

In most cases no. Domestic solar PV systems are usually covered by permitted development rights, provided panels don’t protrude more than 200mm from the roof. Listed buildings, conservation areas and flat roofs may need planning approval — we’ll flag any of this during your survey and handle the application if needed.

How long does the whole process take from quote to switch-on?

Typically around 4 weeks. The site survey takes about an hour, design and proposal usually within a week, and the install itself is 1–3 days depending on system size. We then notify your DNO (the regional grid operator) and your system is live.

Cost & Savings

What you’ll pay and what you’ll save

How much do solar panels cost in the UK?

A typical residential solar system (4–6kW) with a battery costs between £9,000 and £16,000 fully installed, depending on system size, panel choice, battery capacity and roof complexity. Solar-only systems without battery storage typically start from around £6,000. We provide detailed quotes with a full breakdown — no hidden costs.

How much can I save with solar panels?

Most TJS Solar customers reduce their electricity bills by 60–80% over a year. The exact saving depends on your system size, energy usage pattern, whether you have a battery, and your tariff. We’ll model your projected savings as part of the quote so you can see exactly what to expect.

What’s the payback period for solar?

Most residential systems pay back in 6–10 years. Commercial systems often pay back faster — typically under 5 years — because daytime usage matches solar generation more directly. After payback, your system continues to generate free electricity for the remainder of its 25+ year lifespan.

Do you offer finance?

Yes. We work with Phoenix Financial Consultants to offer flexible finance options for residential customers, subject to status and credit checks. This lets you spread the cost over manageable monthly payments rather than paying upfront. We’ll talk you through the options during your quote.

Are there any grants or tax incentives available?

Solar PV and battery storage are currently subject to 0% VAT for residential installations (a saving of 20% versus pre-2022 rates), set to remain in place until at least March 2027. The Smart Export Guarantee pays you for excess energy exported to the grid. Commercial customers can typically claim 100% of solar costs against taxable profits in year one under the Annual Investment Allowance.

Installation

How the install works

How long does the install actually take?

A standard residential install is completed in 1–2 days. Larger commercial installs take 3–7 days depending on system size and roof access. Scaffolding usually goes up the day before, and we aim to leave your property tidy and exactly as we found it.

Will the install make a mess?

No. Our installers protect your property with dust sheets, wear shoe covers indoors, and clean up thoroughly at the end of each day. Most of the work is done outside — the only indoor element is the inverter location and a few cable routes. We treat your home like our own.

Do I need to be at home during the install?

Someone needs to be present to let us in on the first day and at handover, but you don’t need to be there the whole time. We’ll always agree the schedule with you in advance.

Will the panels damage my roof?

No — a properly designed and installed solar system actually protects the roof underneath. We use premium Renusol or Van Der Valk mounting systems with sealed roof fixings. Our installers are MCS-certified and NICEIC approved. We also carry full public liability and professional indemnity insurance for total peace of mind.

Battery & Tariffs

Maximising your savings

Do I need battery storage with my solar?

It’s not essential but it makes a huge difference. Without a battery, any solar you don’t use immediately gets exported to the grid (you’re paid roughly 5–15p per kWh for export). With a battery, you store that energy and use it later — saving you the 25–35p per kWh you’d otherwise pay to buy it back from the grid. Batteries typically more than pay for themselves through this offset.

What is the Sigenergy SigenStor and why do you recommend it?

SigenStor is our preferred all-in-one system from Sigenergy. It combines the inverter, battery storage and EV charging into a single, stackable, modular unit. It’s AI-optimised, has a 10,000-cycle lifespan and up to 15-year warranty, and looks far better than the typical mess of separate units bolted to a wall.

Should I switch to a smart tariff like Octopus Go or Flux?

For most customers with solar and battery, yes. Octopus Go gives you cheap overnight rates (good for charging batteries and EVs), while Octopus Flux pays you peak rates for exporting solar at high-demand times. We help you pick and switch to the right tariff as part of your install — done well, this can save another £300–£800 per year on top of your solar savings.

Can I charge my EV with my solar?

Absolutely. We install EV chargers as part of many of our solar systems — either standalone or integrated into the Sigenergy SigenStor unit. Smart chargers can be set to only charge when there’s spare solar available, giving you free miles from the sun.

Warranty & Aftercare

Long after the install

What warranty do you provide?

Solar panels are warrantied for 30 years performance, inverters typically 10–12 years (or up to 15 years on Sigenergy SigenStor), batteries 10–15 years depending on brand, and we provide a 5-year workmanship warranty on top. Our MCS certification also means your install is backed by industry-level dispute resolution.

Do solar panels need maintenance?

Very little. Rain does most of the cleaning. We recommend a visual check once a year and occasional inverter monitoring via the app. If anything ever stops working as it should, just give us a call — we look after every system we install.

What happens if you go out of business?

Your panel and inverter warranties are with the manufacturers directly, not TJS Solar — so they’re honoured regardless. Our MCS certification also means installs are covered by industry-standard insurance-backed guarantees. We’ve been trading since 2017 (originally as TJS Electrical) and have no intention of going anywhere.

Will my solar system still work in a power cut?

Standard solar systems shut down during a power cut for safety reasons. However, certain battery systems — including the Sigenergy SigenStor — can be configured with backup functionality to keep essential circuits running during outages. Ask us about this if it’s a priority for you.

Commercial

For business customers

How is commercial solar different from residential?

Commercial systems are typically much larger (10kW to 500kW+), use heavier-duty mounting systems suited to industrial roofs, and often pay back faster because daytime consumption matches solar generation more directly. The financial case is also stronger — you can typically claim 100% of the cost as a tax-deductible expense in year one under the Annual Investment Allowance.

Do you only install commercial in the North West?

No — we install commercial solar UK-wide. We’ve completed projects from Lancashire and Cumbria up to Carlisle. Residential is restricted to roughly a 70-mile radius of Leigh, but commercial is national.

Will solar affect my property’s EPC rating?

Yes — positively. Solar PV typically improves a commercial property’s EPC rating by a band or more. This matters increasingly under MEES regulations, which raise the minimum EPC requirement for let commercial property to a C by 2027 and a B by 2030.

Can solar help with our net zero / ESG reporting?

Yes. Commercial solar directly reduces your scope 2 emissions and provides clear, auditable data on energy displaced. For businesses with reporting obligations or supply chain pressure on emissions, this is increasingly a procurement and customer-retention advantage.

Got a question we haven’t answered?

Pick up the phone or send us a message — we’d much rather give you a straight answer than have you guessing.

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