Hotwire offers two kinds of diversion loads; a resistive load bank or 12/120 dual voltage water heater element. The resistive load consists of 4) wire wound ceramic power resistors mounted onto a phenolic plastic board. About the size of Nigel Calder’s book, “Mechanical and Electrical Handbook” (you do have one don’t you?), it should be mounted where fabric will never come against it.
The 12/120 volt water heater will fit most US made water heaters with one inch by 11 threads, including at least most Seaward, Raratan, Force 10, and Torroid and others. And, with an adaptor for the 4 bolt flange, Atlantic, Allcraft, Atwood, and others with a four bolt flange. At least some of the time you will get at least warm water from the excess energy from your wind generator.