Help with your gas and electric bills

I found out yesterday that if you are on any benefits or you are classed as disabled or get £13,000 a year or less you could get up to 20% of your bills no matter how you pay.I'm with n power for gas and electric an pay by direct debit they give me a £100 back a year for direct debit payments but now i also will be getting 20% off my bills as i receive income support i also receive disability but they don't take that into consideration.I hope this will help you as i know money is tight everywhere