What is the GreenShed project?
Taking advantage of routine periods when cattle are housed, for example when over-wintering to protect the ground, or in beef finisher units, SRUC are testing a concept to ‘enclose’ the livestock shed, to contain and capture the methane as it comes from the animals. The enclosure isn’t air-tight, but still allows us to extract air to create a slight negative pressure inside the shed which prevents methane escaping to the atmosphere.
The methane rich extracted air can then be treated in a single, centralised place to capture the methane. This is designed around retrofitting an existing shed, using impermeable, removable curtains to do the enclosing.
Manure from the animals is used to feed a small anaerobic digestion (AD) plant to produce electricity and heat to run the system. Further modules can be attached to the system to increase sustainability and profitability; a plasma reactor to produce more crop-available nitrogen from the digestate potentially trebles the available nitrogen; and a vertical polytunnel for growing high value fresh produce uses the available heat from the AD system.
Obviously, this system is not cheap, but with a willingness from some consumers to pay a premium for sustainability, a relatively modest “GreenBeef” premium that feeds back to the farmer could cover the additional costs for beef enterprises.
This first proof of concept stage was funded by Scottish Government, and carried out at the SRUC GreenCow facility. Based on these initial findings, this work is now being taken forward into a larger pilot project which will support further design and development of the GreenShed concept.