Solar panels are one of the best ways to reduce your energy bills in the UK, but they’re famously not the most affordable. The average 3 kilowatt-peak (kWp) solar panel system costs around £9,000, which can be a significant outlay for many households around the country - and this is why people are often tempted by cheap solar deals. 

However, solar panels are meant to be a long-term investment - something that you eventually recover the cost of via energy bill savings, and something that will last you at least 25 years. Cheap solar panels might never make it this far. 

We’ll explain exactly why cheap solar panels aren’t worth the risk, as well as give you tips on sensible ways to reduce the cost of solar panels.  

If you’d like to find out how much a solar & battery system could save you, just answer a few quick questions below and we'll immediately generate an estimate for you.

Should you buy cheap solar panels?

Cheap solar panels are never worth the risk. A cheap price either means the hardware is low quality or the installation is low quality - or both. And this will cause you many problems further down the line (if not immediately). 

If you’re wondering what ‘cheap’ means in the context of solar - speaking very roughly, a 3kWp solar panel system is about £9,000, or £11,000 if you add a 5kWh battery. If you’re seeing prices that fall dramatically under this level, you should start being a little cautious.

Why are cheap solar panels risky?

The installation of cheap solar panels comes with a whole host of risks, including:

• Low efficiency and low power output
• Maintenance issues
• Poor performance in higher temperatures
• Unattractive appearance
• Short lifespan
• Poor customer support

Let’s delve into these issues in a little more detail.

Low efficiency and low output

If the low price is due to poor quality hardware, you could end up with solar panels that don’t have a very high efficiency rating. In the context of solar, ‘efficiency’ refers to the percentage of natural light that the panels can convert into useable electricity. It’s pretty standard for most residential solar panel installations today to exceed 20% efficiency - anything much lower than this should raise a few alarm bells. 

Similarly, poor quality panels may also have a low power output rating. The power output rating refers to the maximum amount of power that a solar panel can generate in ideal conditions, and the best panels on the residential market today are around 400 watts (W). 

If you cover your roof in solar panels that have low efficiency and low power output, you’ll see much smaller savings on your electricity bills. 

Maintenance issues

Solar panels are associated with the phrase ‘fit and forget’, which refers to their minimal need for maintenance. You’ll get that if you buy high-quality solar panels from a trusted installer, but not if you opt for something cheap. 

Cheap panels will malfunction more often because of their lower build quality— and that means spending more on repairs.

Poor performance in higher temperatures

Most solar panels start to see decreases in efficiency once temperatures exceed 25°C, and this is completely normal, but cheap solar panels will see more dramatic declines. This decline in efficiency is called the temperature coefficient and it’ll change depending on the quality and type of the solar panel. 

Higher quality solar panels will typically see efficiency reductions of 0.3% to 0.5% for every degree above 25°C. However, lower quality solar panels will see much bigger drops in efficiency once the mercury starts to climb. It’s in the summer months where you would naturally expect your solar panels to be at their most productive, but this won’t be the case if your system is practically wilting in the heat. 

Given that UK summers are expected to become hotter and hotter, it’s particularly unwise to invest in hardware that isn’t built to survive in temperatures above 25°C.

Unattractive appearance 

Unsurprisingly, the best looking solar panels on the market tend to come at a bit of a premium - they’re usually made of monocrystalline silicon, all-black in appearance, and look very impressive on most residential rooftops in the UK. 

In contrast, most cheaper solar panels are made of polycrystalline silicon, which has a distinctly mottled blue appearance, and is often the reason solar panels have traditionally struggled to offer much curb appeal. 

If you’re particularly bothered about having a solar panel installation that looks sleek and stylish, cheap solar panels are unlikely to tick that box.

Short lifespan

Good quality solar panels typically come with a 25-year warranty and are expected to last beyond this point, sometimes up to 30 years or more. This lengthy lifespan is pretty important given how most people view solar panels as an investment that will eventually ‘break even’ and lead to pure profit. 

For instance, the average UK household with a solar & battery system will break even in around nine years. This estimate is based on 40 of Sunsave’s own solar & battery system designs on rooftops all over the UK (every system uses 430W solar panels and a 5kWh battery, and is signed up to the Octopus Intelligent Flux tariff). 

Meanwhile, with cheaper solar panels you might never break even or make it to the 25-year mark, and the panels are unlikely to come with a decent warranty.

Poor customer support

Buying solar panels from a budget installer will likely leave you with poor post-installation customer care. It could even be non-existent, so if something goes wrong with your solar panels you’ll have to spend time finding someone else who can help you. Once you’ve found some assistance, you could then have a pretty expensive time calling someone out to fix your system. 

By opting for Sunsave Plus, you’ll get a 20-year monitoring & maintenance support package, which means you won’t have to worry about extra hassle or exorbitant fees if and when your system needs some attention.

Sensible ways to reduce the cost of solar panels

If you are struggling to cover the high upfront cost of a solar & battery system, there are better ways to keep costs down than simply opting for a low quality installation. For example:

• Consider a solar subscription – Sunsave Plus is the UK’s first solar subscription, and it means you can get a top-quality solar & battery system at no upfront cost, and instead spread the payments across 20 years. 

• Check if you’re eligible for grants – you might be eligible for the government’s ECO4 scheme, which was set up to help low-income homes make efficiency improvements. If you’re eligible, you could get funding towards a solar panel system, or have it paid for outright.

• Consider buying panels through Solar Together – Solar Together is a group-buying scheme designed to help homes install solar panel systems at a reduced cost. This is generally 30% to 35% lower than the average market price.

Cheap solar panels: FAQs