Which Mibec pre-insulated pipes are best for Commercial RHI projects?
The RHI or Renewable Heat Incentive, is a government backed scheme designed to encourage the use of renewable technologies, in both the Domestic and Non-Domestic Sector. The RHI will provide finance in the form of a tariff scheme, which will be paid, usually to the owner, for up to 20 years in Non-Domestic and 7 years in domestic.
Underground pre-insulated pipes are used to connect the renewable heat source to one or more buildings on the site. The pre-insulated pipes are designed to maintain the water temperature when in transit (avoiding heat losses to improve energy efficiency). At Mibec we can supply a wide range of pre-insulated pipe products from leading district heating pipe manufacturers like Rehau, Microflex or our own Mibec DHP pipe. All Mibec pre-insulated pipes are fully approved for use in RHI schemes through compliance with the requirements of EN 15632, a standard agreed by OFGEM that enables use of plastic insulated pipes to be considered for RHI use. By meeting this standard OFGEM consider the products to be “properly insulated”.
However the technical specification of the pre-insulated pipe selected can contribute towards the actual level of RHI payments received by the owners even if the pipe meets the requirements of EN 15632 and is considered to be “properly insulated”. In the Non-domestic RHI guidance volume 1 (section 13), the heat losses can be disregarded where the annual average heat loss in kWhth from all external pipe lengths that are “properly insulated” and greater than 10m in length is less than 3% of the projected annual output of the plant in kWhth. If this 3% requirement is not meet and heat losses have to be taken into account it will impact on the level of RHI payment ultimately received by the owner. When specifying the pre-insulated pipe this factor should be taken into account and in some circumstances to meet the 3% heat losses a higher performance product like Rehau Rauthermex with its low heat loss polyurethane insulation should be used.
For example we offer both Rehau Rauthermex and Rehau Rauvitherm in our range. They are both “properly insulated” fully meeting the requirements for consideration in RHI. However, Rauthermex has a lower thermal conductivity than Rauvitherm (lower the better) making it much more likely to meet the 3% target.
Although the upfront costs can be a little higher for Rehau Rauthermex than some of the other pre-insulated pipes in the range, potentially having increased levels of RHI payments can make the slightly higher capital cost a very sound investment in the longer term for the client. Depending on the nature of the renewable heat source and the pipe layout and length, products like Rehau Rauvitherm, Microflex and our own Mibec DHP pipe may still have heat losses below the 3% potentially making them the better choice financially. The key message is to do the maths around the heat losses for your project at specification stage and select the pipe product which gives the best ROI for the client, ensuring they get the most benefit from their RHI application.
At Mibec, we offer a full free of charge specification service covering the whole of the UK, designed to support architects, specifiers or contractors, helping you to select the right pre-insulated pipe solution to meet your needs. Please feel free to email or call our support department on 01948 661639 where one of our trained advisers will be happy to help you.