LV 1500 is a very small and efficient hydro power generator (max. power 1500W) made by Hydro Induction Power, a company based in Redway, CA http://www.homehydro.com/.
The LV1500 re are 12V / 24V / 48V models build around a stainless steel Turgo runner, a brushless alternator and a rectifier.
Impressive is the that it works with 60 to 600 feet Head range and 5 to 100gpm Flow range.
For a greater energy need ( max. 4KW) they offer also another product range here: http://hipowerhydro.com/
The Passive House Institute of Germany develops solutions for a higher grade of enegy efficiency in housing business.
The Passive House is a building standard that is truly energy efficient, comfortable and affordable at the same time.
The firstpilot project ( Kranichstein Passive House, Darmstadt, Germany, 1990) was Europe’s first inhabited multi-family house to achieve a documented heating energy consumption of below 12 kWh/(m²a), a consumption level confirmed through years of detailed monitoring.