Your choices so far:
1 Process heat/steam (50 - 150 °C); 2 District heating
| What is your resource? | What do you want to deliver? | What is the service the customer wants? |
| Biomass (digestible sludge) | District cooling | Comfortable indoor climate |
| Biomass (fermentable sludge) | 2 District heating | Electricity |
| Biomass (solid) | Electricity | Process cooling (< 0 °C) |
| Geothermal | Fuel: Gaseous | 1 Process heat/steam (50 - 150 °C) |
| Sunshine | Fuel: Liquid | Process heat (150 - 1000 °C) |
| Water | Fuel: Solid | Process heat (> 1000 °C) |
| Wind | Local cooling (ind. house) | Transport |
| Residual oils/fats etc | Local heating (ind. house) |
District heating is distributed by the aid of hot water or, in some cases, steam. Most common is the distribution of hot water. Steam-based systems may be of interest in case there is a sufficiently large industrial demand for steam – for example at a brewery or any other food processing industry – nearby the central energy production plant.
For the customer one main advantage with district heating as compared to individual heat production is that the responsibility is handed over to a central, large-scale, production plant with 24-hour manning and professional personnel. Thus, the risk for breakages and un-planned stoppages is minimised. The price paid is, of course, a fixed fee.
From a resource economy point of view, replacing electricity consumption for low-temperature processes by delivery of a low-exergy energy carrier and electricity production in high-efficiency plants is a step towards sustainability.
Biomass-fired tri-generation, simultaneous production of heating, cooling and electricity, is already successfully installed in a number of Swedish cities and can be seen in full, commercial operation.
For process heating to be viable it is obvious that the industrial site must be located within reach for the district heating network.