How do you make a heat net-work?
Traditional horticultural heating systems are generally self-contained, comprising an energy centre fitted with boilers or CHP providing heat to several greenhouses or climate zones. In simple terms, this can be considered a heat network, but the concept of heat networks is wider than this and is generally taken to mean a heat provider distributing heat to a number of users (who may or may not directly pay for the heat).
What is a heat network?
As the variety of heat sources available to growers increases, including biomass, AD plant, surplus process heat, heat pump systems, etc., growers may find themselves at the receiving end of a heat network. Alternatively, horticultural sites with a large heat demand but with some spare capacity could become a hub for the provision of heat into a local heat network.
Most simply, a heat network consists of a centralised heating asset connected via underground pipework to multiple users. These can vary widely in complexity, size, and heating technology. Although the concept is simple, problems often occur if the system is not both designed and operated correctly. This means proper sizing of the heating assets, pipework, and operating temperatures. This tech update explores some of the aspects that should be considered when aiming to benefit from a heat network, as both a heat user and a heat provider.
Greenhouse sites as heat users
When connecting to a heat network, you should carefully consider the availability of the heat. This will come down to both the energy centre and the other connections on the network – where is the heat coming from and who else is using it?
Greenhouse sites as heat providers
Essentially, any site with a heat demand provides a potential connection to a heat network: from a nearby growing site, other commercial heat users, or local domestic properties.