Biomass combined heat and power (CHP)

Read these pages for a detailed look at biomass combined heat and power (CHP), the three types of biomass CHP boiler systems, the pros and cons of each and the implications of biomass CHP for CO₂ enrichment.

There are horticultural projects where a biomass boiler also enables power generation. This process allows simultaneous generation of usable heat and electricity and is known as biomass combined heat and power (CHP).

By using some of the gas released by wood, or heat created from a biomass boiler, a biomass CHP system drives a generator or turbine. The remaining thermal energy can then be used to heat a glasshouse or some other process.

Biomass CHP currently qualifies for subsidy for both the heat and electricity produced. This makes it a potentially attractive investment proposition, where there is a consistent and sustained demand for heat, providing the electrical power produced may be utilised on site or exported to the grid.

The usual starting point for a cost-effective biomass CHP installation is the requirement for heat. This is due to all biomass CHP systems producing a higher proportion of heat than electrical power. The resulting electrical energy is then used to either reduce dependence on power from, or for export to, the grid.

The three types of biomass CHP currently available are gasification, steam turbine and ORC turbine. These vary considerably in technology, scalability and in the proportion of heat and electrical power produced.

CHP unit on a protected edibles site

Image courtesy of NFU Energy.

Learn about gasification in the context of biomass CHP, the typical outputs and costs and the pros and cons of gasification. 

Find out about biomass steam boilers, their typical outputs and costs and the pros and cons of using a steam turbine in your biomass CHP system.

What is an Organic Rankine Cycle (ORC) system and how is it different to a steam turbine? Learn about the typical outputs and costs and the pros and cons of using an ORC turbine to power your biomass CHP installation.

Read about biomass CHP and the implications for CO₂ enrichment in the glasshouse.