Combination Solar Wind Power Systems For Self Sufficient Living

Combination solar wind power is ideal for self sufficient living in off the grid situations where deep cycle battery storage is required. However, the addition of a wind generator to solar photovoltaic arrays in grid tie (grid interactive) systems is most likely overkill and does create complications.

The critical difference between the two situations i.e. self sufficient living off the grid vs grid tie is the issue of storage.

In self sufficient situations -off grid - the storage of energy in deep cycle batteries is essential. Looking after those batteries to ensure long life becomes a key concern. That's where combination solar wind power helps. Nature provides a "match made in heaven"...

The two energy sources are complimentary, together they create a synergy that spells longer life for deep cycle batteries.

Getting hard data on the relationship between the distribution of solar energy and wind energy is difficult but there are some generalizations we can make:

  • Summer is generally the time for peak output from solar while winter is more likely the season for peak wind energy.
  • Situations where there is neither wind power nor solar power are rare - there's usually one or the other.
  • Wind energy is available on many nights.

More telling is the actual experience of people who live with combination solar wind power systems. A common observation is that wind power from a smallish (1 kW) wind generator will approximately equal the output from a 500 W solar array over a year.

The distribution of the two energy sources reduce the number of "battery cycles" - the ultimate measure of battery life. There's also another gain for battery condition:

Batteries "enjoy" a greater rate of input than that typically available from a solar panel array alone. Deep cycle batteries are quite happy with inputs of up to 10% of their rated capacity e.g. a 1000 Amp hour pack will happily accept 100 Amps. On windy, sunny days with a combination solar wind power system the deep cycle battery pack can receive vigorous charges and "equalizing charges" that extends battery life.

For average off-grid installations solar panel arrays are well complemented by wind power and the better distribution of energy input will pay back with longer battery life.

For good information on deep cycle batteries see:

Combination Solar Wind Power For Grid-Connect Systems?

Thanks to global warming concerns there has been a significant shift toward more sustainable thinking. Many governments are now offering rebates as incentives for solar panel installation in mainstream grid-connect systems so they are becoming popular.

A question that arises is whether combination solar wind power is viable for grid interactive systems. The short answer is no based on cost-benefit analysis. In the case of grid interactive systems the grid acts as the battery so the real need for better energy distribution is eliminated. There are companies marketing the concept and turbines for residential roof top wind power but the idea is deeply flawed in all but ideal wind sites.

Wind generators also require different (currently more expensive) grid tie inverters so cannot simply be added to existing grid interactive solar arrays.