Your choices:
1 Process heat/steam (50 - 150 °C); 2 District heating; 3 Biomass (solid)
| 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 |
| 3 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) |
The most practical fuel – from a storage and handling point of view – is solid biomass of some quality that is easily available in the region and that can be stored without excessive risks. However – also other renewable energy resources like solar heating, biogas or geothermal energy may well be integrated in the system, but the base-load fuel would usually be solid biomass. In such cases, when a mix of renewable resources are used for the production, these will also be the renewable resources used for district heat production and hence for the industrial process itself.