So no electricity provider can promise you that all your energy comes from a renewable source. Instead, energy companies can use a Renewable Energy Guarantee of Origin certificate from Ofgem, which shows how much renewable electricity they've bought and sold to customers.
With OVO Greener Energy, although we can't guarantee that all the electricity is from renewable sources, we can show that for every unit you use, we've bought the same amount of renewable electricity.
Baffled by biomass? Stumped by solar power? Discover how wind turbines harness the free power of the wind to create electricity, and what gets burnt in biomass energy production. And while we're on the subject of words beginning with bio, check out this section for information about biofuels including biodiesel, bioethanol and biogas.
If you like the idea of generating your own electricity and perhaps even earning money from it, solar panels may be the answer. There are two different types: photovoltaic solar panels (also known as solar PV) and solar thermal.
If you want to know how they work, how you could earn income
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