Economic Calculations
An economic analysis should be done for each microturbine installation. The key factors to consider are:
Fuel costs (variable)
Maintenance costs (variable)
Capital cost (fixed)
Finance cost (fixed)
Local electricity costs
Benefits of cogeneration

The total costs of running a microturbine should be expressed in terms of $/kW-hours. This can be compared to the local electrical tariff rate to determine economic viability of a project. Any cogeneration should be expressed in terms of kW/hour if the thermal load is currently supported by electricity.

What are applications that make economic and operational sense?
Cogeneration end users are typically looking for a 3 to 5 year payback periods on a microturbine purchase. By adding a cogeneration aspect to the project additional economics can be realized. In most cases the economics of a microturbine are only realized when the thermal energy is used. In Europe, non-cogeneration installations are almost never considered. Energy is expensive in Europe and most other places in the world. An exception is France, where a large majority of the electricity is generated from nuclear energy.

What electricity cost per kW hour makes an installation of a microturbine attractive?
There are no set $/kW level that will determine if a microturbine project is attractive. One needs to compare fuel and electricity costs. When compared on an equal basis the difference between electricity costs and fuel costs is called the 'spark spread.' A positive spark spread occurs when electricity is higher in cost per unit than fuel. The higher the spark spread the more attractive it is, economically speaking, to install a microturbine.