- Free electricity. You could typically slice your electricity bill by £90- £180/year – more if you're at home during daylight hours or prices jump significantly, which they could well do over 25 years.
- Try free then buy. One free solar panel scheme, Eon, allows you to buy the solar panels at a reasonable price later on, meaning you could decide later to pump in the cash and keep the feed-in payments.
- Make your home greener. Free solar panels let you make a contribution to reducing your home's carbon footprint, without stumping up your own cash. But not everyone's convinced about solar panels' benefits – see George Monbiot's Guardian blog.
- Free maintenance. Usually the free solar panel company maintains the panels and pays for insurance (always check your contract).
- They keep the feed-in tariff
The free solar panel company keeps the feed-in tariff, typically £1,100-ish year. If you've spare cash, you may be better off paying for your own system. Yet if you don't have spare cash for panels, you wouldn't been able to get this anyway.
- Buyout fees
This is best for those settled in their forever home. While some providers have reasonable buyout fees, with others, it's cheaper to buy out Lionel Messi.
- Potential buyers may be wary
Do bear in mind a leased roof could ring alarm bells for prospective buyers. Richard Webster of Richard Webster & Co Solicitors says: "I can't see any real problems for the average buyer with the free panels scheme, other than the look of the house, if that's a concern.
"Most people will appreciate even a small saving on electricity costs. Of course, there is always the chance that some buyers may worry; being tied to some third party in a contractual situation, however harmless, could frighten some."
- Roof repairs could be costly
Free solar panel companies usually fix your roof if it's damaged by the panels. But if you want to fix your roof for a reason not connected to solar panels, free solar panel companies sometimes make you cover their feed-in payments in the meantime (always check).