can use wind power?
If you live off-grid, chances are the bulk of your energy
will come from solar. The generator will supply the bulk of
the rest of your energy that solar doesn't provide. A wind
turbine is only useful if you can use it to offset how much
the generator runs, how deeply the battery gets cycled, and
to fill in the gaps when you have poor solar conditions. In
the summer a wind turbine is rarely needed for off-grid power
if you have installed adequate solar generating capacity.
In the winter, however, when the days are short in the higher
latitudes, a wind turbine can be a valuable asset and save
hundreds of hours on your generators and prevent deep cycling
your battery. In other words, the wind power supplements the
solar in winter time when the days are short. In summer the
wind turbine is of little use, and is not really needed.
turbines are not cheap. They cost over 3x per kWh
what solar power costs, and the tower is the most expensive
component of a wind power system. Therefore, the need for
a wind turbine for off-grid power must be carefully weighed
against generator and battery cost in the long term. Wind
turbines for grid-tie applications are not practical at all
for residential power. I provide no support,
nor do I build any turbines, for people that have grid power
and want or use a wind turbine.
have designed, built and tested several models over the years,
however at the present I only build parts for two models -
the DWP260 and DWP350. I provide an energy rating for my turbine
designs at 5.0 m/s (11 mph) average wind speed because that
is the most common average wind speed on a windy day. Peak
power means almost nothing with wind turbines because the
wind rarely blows hard enough to make peak power a practical
rating. So a wind turbine that is advertised as 2 kW really
ends up being a 200 watt turbine at the average wind speeds
most sites experience.
The DWP260 is a 2.6 meter (8.5 foot) diameter
turbine designed specifically for 24V systems. It operates
at 100 volts open circuit and is designed for use with a Morningstar
Tri-Star MPPT60-150V controller. It will produce 2.9 kWh/day
@ 5.0 m/s wind speed. It uses either commercially available
fiberglass blades or hand carved wood blades, and a simple
20 pole generator that is much cheaper to build. This turbine
is suitable for wire run distances that do not exceed 100
meters on 24V systems. It will produce 1.2 kW peak power.
DWP350 is a 3.5 meter (11.5 foot) diameter machine
for 24 or 48V systems. It operates at 150 volts open circuit,
so can be used on wire runs up to 300 meters from the tower
to your power room. It is designed for use with a MidNite
Classic 150 MPPT controller. The 350 is a more advanced turbine
with a more expensive 20 pole three-phase generator. It can be
used with either commercially available 3.2 meter fiberglass
blades, or hand carved 3.5 meter wood blades. It is considerably
more powerful than the DWP260 and produces 4.4 kWh/day @ 5.0
m/s wind speed. It will produce 2.2 kW peak with 3.2 meter
fiberglass blades. With 3.5 meter blades it will produce 2.5
kW peak on 24V systems, or 3.0 kW peak on 48V systems.
on below if you want more information on these turbines, and
check out the Homebrew Off-Grid Projects link above.