Your choices so far:
1 Fuel: gaseous; 2 Comfortable indoor climate
| What is your resource? | What do you want to deliver? | What is the service the customer wants? |
| Biomass (digestible sludge) | District cooling | 2 Comfortable indoor climate |
| Biomass (fermentable sludge) | District heating | Electricity |
| Biomass (solid) | Electricity | Process cooling (< 0 °C) |
| Geothermal | 1 Fuel: Gaseous | 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 energy service "comfortable indoor climate" is best provided by district heating and cooling systems unless in sparsely populated or rural areas. For isolated houses the situation becomes different and gas heaters and/or electrical AC-units are often used. For the production of tap water gas-fired heaters are commonly used in the European continent.
In the case of CHP or tri-generation based on gaseous fuel, the gas will normally be drawn from the European gas grid and this will also be the case for a majority of the gas-fired tap-water heaters found throughout the European continent.
With the present availability and reliability offered by the gas grid, local production of space heating and tap water from gas is a good and versatile system.
However: With the global warming the need of cooling during summers is increasing and as long as the cooling is provided using individual air-conditioning units the need for electricity is bound to increase and to become more and more seasonal.
Therefore, with individual houses, gas from the gas grid is a suitable alternative for heating and tap-water production and individual AC-units are suitable for cooling, but in densely populated areas these systems should be replaced by tri-generation systems providing district heating and district cooling.