Shaw Renewables the bioenergy specialists

New Boiler, Same Tariff


It’s been just over 6 months since new RHI rules were introduced that allow broken or underperforming boilers to be replaced without effecting the RHI tariff you receive – we give a brief overview and address some frequently asked questions.

Plant Replacement Overview

Before these rules were introduced, a broken system would be worthless – your investment would never see a return and if you did replace your boiler you would receive the current tariff payments, which for some offer significantly reduced quarterly payments. This left some biomass boiler owners scrambling to keep their poorly designed systems running, spending thousands each year to keep their boilers limping through the quarterly payments.

As of October 2018 your underperforming, over or undersized or broken renewable energy plants can be replaced without huge losses or a reduction in your tariff payments.

When an original installation breaks down. Participants will be allowed to replace their plant with a new ‘like-for-like’ replacement – ‘like-for-like’ refers to the technology type and capacity. Replacement plants will be able to maintain their original RHI tariff for the remainder of their participation on the scheme.


Q. What are acceptable reasons to replace my boiler?

A. Ofgem lists the following accepted reasons to apply for a boiler replacement:

  • Poorly designed system is causing downtime and inefficiencies in the heating system
  • Boiler itself has broken down, worn out or has been destroyed
  • Your boiler was oversized and is working inefficiently
  • Your boiler was undersized and not meeting demand
  • You require a change of fuel (this must be like-for-like, for example wood chip for wood pellets)
  • Moving premises – Ofgem allow you to take your boiler with you.

Q. Do I have to install the same boiler make and model?

A. No, you do not have to install the same boiler make and model, you are even permitted to switch to a different form of RHI eligible wood fuel. You are only required to install the same technology, if you had a biomass boiler, you must install a biomass boiler and if you had a heat pump you must install a heat pump.

Q. Can I continue to use the generated heat for drying wood?

A. Each boiler replacement is classed as a new installation, which must comply with the eligibility rules set out at the time of the replacement. As drying wood is no longer an eligible heat use under Ofgem regulations, your replacement would not be accepted.

Q. My heating system is incorrectly sized, can I replace the boiler with one that has a more suitable capacity?

A. Yes, your replacement boiler can have a smaller or larger capacity than your original. There are limits to the amount that your replacement boiler can earn, so it would be worth discussing if staying on your original tariff gives you more return for your investment than the current tariff.
You can find out more about changing boiler capacity here, on our RHI Plant Replacement Page.

You can find out more about Plant Replacement rules here, on our Biomass Boiler Replacement page.