Bulb Energy
I've changed my energy supplier to Bulb. You can get a quote using my link. If you choose to accept their quote and change your supplier to them and use my referral code (link) we both get £50 credit in our Bulb account. I was a bit unsure about doing this myself but once I did it, I couldn't believe how easy and painless it was. Literally less than 5 minutes. They took care of everything, contacting my current supplier and sorting the change. Their prices, although I've been told go up and down, are cheaper than what I paid with my old supplier. So, all's good.
Use this link:
Update: I’ve moved house now, not with Bulb now. But I would still recommend them