Studies of popular renewable energy systems show that cumulative energy demand (CED) can be understood as a kind of simplifying life cycle assessment [1] where the accounting of energy and material inputs is seen as part of an inventory analyses and the calculation of CED as a rough form of...

The cumulative energy demand and the energy yield ratio can be seen as an indicator of environmental impacts to estimate the depletion of energy resources considering a whole lifecycle. For two wind energy converters (1.5 and 0.5 MW) these figures have been calculated. For calculating energy...

In view of the currently observed energy prices, recent price scenarios, which have been very moderate until 2004, also tend to favor high future energy prices. Having a large impact on energy-economic scenarios, we incorporate uncertain energy prices into an energy systems model by including a...