Your choices so far:
1 Biomass (fermentable sludge); 2 Fuel: liquid
| 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 |
| 1 Biomass (fermentable sludge) | District heating | Electricity |
| Biomass (solid) | Electricity | Process cooling (< 0 °C) |
| Geothermal | Fuel: Gaseous | Process heat/steam (50 - 150 °C) |
| Sunshine | 2 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) |
While fermentation of sugars may yield alcohol (ethanol) concentrations about 15%, at the very least 45% is required to make the ethanol a combustible fuel. And only at even higher concentrations can it be combusted without preheat. To be viable as a commercial fuel, the alcohol concentration should exceed 80% but usually there is no reason to stop the distillation until 95% is reached.
Ethanol can be mixed into gasoline and is so, but it can also be used as a stand-alone fuel. However, the cost for the fermentation and especially for the distillation are usually prohibitive for the use of ethanol outside the transportation market.
The flame temperature of ethanol with about 5% water is around 1800 °C but since ethanol is a strong solvent for many qualities of plastics it is a complicated fuel to use. In many practical cases, most of the fuel distribution and transport systems must be changed to be able to cope with ethanol and in combination with the price for the fuel as such it is only scarcely used as a stand-alone fuel.
Ethanol is not well-suited for local electricity production so a customer requiring the unique properties of electricity would not be likely to buy ethanol to supply their need.