Sorry Facty,I just saw this report about a Conergy...

Sorry Facty,

I just saw this report about a Conergy solar/wind/diesel hybrid system in Greece. Basically the inverter self-adjusts to minimise use of storage during the day to get maximum efficiency from the DC renewables and uses battery through the inverter to give AC at night.

How much better to use a larger solar/wind source to both supply the household during the day AND to charge the battery so that the diesel doesn't have to run at night. Then run DC power through the inverter.

The outstanding charge/discharge cycle efficiency of the vanadium flow battery VRB-VESS! is perfect for this.

I want an holiday in Greece! Do you reckon those two cute German telephonists I met in 1980 would still be on the Isle of Capri?

http://www.solarbuzz.com/news/NewsEUPR268.htm

"Hamburg, Germany: Conergy Completes Off Grid Hybrid Solution in Grammatiko, Greece

This week, Conergy completed a hybrid solar and wind power off-grid solution with combined DC and AC integration in Grammatiko, Greece. The system covers the entire power supply of a 500 m² residential building within a 15,000 sqm property including water-treatment pumping as well as refrigeration.

The challenge for hybrid systems is to simultaneously integrate sources of direct current, such as solar generators, and sources of alternating current, such as diesel and wind power generators. In ordinary hybrid systems all renewable energy sources are integrated either on the DC or on the AC side, therefore the current must pass through two converters.

A significant disadvantage of this is that the two-stage conversion greatly reduces the effectiveness of the overall system. The combined DC/AC integration of the Conergy ISA 30K hybrid avoids this two-stage conversion. This ensures maximum DC charging efficiency (PV to battery) of up to 98% as well as highly efficient coupling of AC sources like small wind power on the AC side.