The RHI has not yet arrived for domestic installers of Solar Thermal but a grant of 300, known as the Renewable Heat Premium Payment is available for domestic customers from 1st August 2011 which is intended to bridge the gap until the full Renewable Heat Incentive scheme is launched in October 2012.

For commercial customers the RHI opened for applications on Monday 28 November 2011 and offers payments on a quarterly basis for heat generated over 20 years based on 8.5p for every kWh of measured heat delivered up to a cut off size of a 200kWp project. 

RHI Payments come directly from the UK Government administered  by Ofgem and their web site has a useful FAQ section on the RHI, click here.

Chart showing the 100% increase in heating oil prices in the UK for three years to March 2012: source