FAQ

How much space is needed and consumed for Renewable Energy?

The space involved for using renewable energy and therefore its efficiency is varying according to the different kind of energy as shown below (South Germany region):

Wind Power:

Approx. 400 – 2000 MWh per hectare, considering clearance areas (however: soil area not permanently used can be used for farming/forestry) or 20.000 MWh per hectare soil area permanently used (foundations etc.).

Solar Power:

Approx. 500 MWh (crystalline modules) per hectare soil area permanently used.

Biogas:

Approx. 20 MWh per hectare soil area (electricity), if heat available for 3rd party is completely used: approx. 30 MWh total energy / hectare

Biofuel:

approx. 3 MWh per hectare, max. energy use (incl. Heat) approx. 7 MWh per hectare

 

Pro‘s and Con‘s of individual technologies in relation to land use and economy:

Ground-mounted solar power:
Pro’s: silent, practically no emissions, deployment of biodiversity below mounting systems, no fertilization, ecological upgrading, efficient climate relief, little economic risks of energy input versus market volatility of energy products, high operating stability, easy renaturation because of simple mounting construction (ram posts), no inherited waste as steel, alu, copper is used and modules are taken back for recycling (guarantees of manufacturer)

Con’s: Assessment of acceptance and aesthetics (planting measures), legal restrictions, volatile energy resource

 

Wind energy:
Pro’s: Cultivation of non-used area, no price uncertainty of primary energy, high operating reliability, low electricity production costs, high space efficiency, Avoidance of peak load electricity

Con’s: Consideration of acceptance aspects (odours, traffic). Possibility of environmental impacts

Biogas plants:
Pro’s: Supports agricultural business, produces base load electricity, usage of organic residues, efficient energy production through combined heat and power
Con’s: Consideration of acceptance aspects (odours, traffic). Possibility of environmental impacts

Biomass plants (wood firing):
Pro’s: Benefit to forestry, produces base load electricity, efficient energy production through combined heat and power, usage of organic residues not suitable for biogas process, high potential for regional value added
Con’s: Consideration of acceptance aspects (emission, traffic). Limited Potential of raw material (sustainable cultivation necessary)

 

What about reliability and the ability to store the energy produced?
PV and wind power are currently adapted to moderate peak load management thus serving to limit price ranges at the electricity exchange. Short frame storage devices with battery systems are already enlarging the usage period of volatile energy sources, especially for isolated grids and to increase own power consumption. Near term e-Mobility devices will serve as a mobile storage system for several hours. Prospectively yet not far away the natural gas grid will be the prime system for energy storage while feeding in bio methane generated by solar and wind energy plants. Generation of bio methane with an efficiency of 60 – 65% will keep the leadership of wind and solar long term. Until then biomass will be the most flexible and economic viable energy storage.