We live in a very windy area and have Tesla Solar with 2 powerwall 2 units. I believe if we added a couple of small wind generators (may have to look like yard are to pass HOA) we could be off grid and charge our car at home more. Can you send the details and/or diagram of your system or suggest someone to contact to work on our system? Thank you! Yours is the first system I have seen where everything it elegantly integrated. Mitch
My email is mitch at mitchrice dot com
Being off-grid in an all electric home, with electric vehicles is going to be very challenging. There are 100,000 BTUs per therm of natural gas. There are 91,740 BTUs per gallon of propane. There are 3413 BTUs per kilowatt hour of electricity.
Comparing electric home heating to combustion is not intuitive because it takes a large quantity of electricity to create the same amount of heat as combustion, but because electricity can be made by renewable sources, when it is sourced that way it remains the environmentally better way to do it. This is our approach. We also live in a much colder climate than you do in Santa Rosa, CA. Here in Cheyenne, WY we get real winter with typically a week or two of arctic cold temperatures.
If on the other hand, you heat your home with combustion and/or are in a warmer climate, which you are, the amount of electricity and storage you need is very different than us. One of the things to do is to quantify your present and projected electricity consumption. An off-grid home needs to have enough battery storage to cover the longest anticipated period of low gain, or no gain days, during the highest rate of electricity usage during the year. For us, that would be ideally be 5-7 days during the coldest part of winter.
Something to keep in mind with wind turbines, usually, HOA are not very accommodating of them. We live in an area where generally the minimal lot size is 20 acres, and ours is smaller, "grandfathered" in, with only 9.6 acres. Still, there is enough distance between us and our neighbors so that neither noise nor wind obstructions are much of an issue. We still checked in with neighbors and got their blessings before installing them. They appreciated the courtesy and concern. The result is we are not having to deal with the kinds of resentments others in other locations have had to cope with. Ideally, wind turbines should be at least 300 feet from the closest wind obstruction. Our original two turbines were sited 80 and 160 feet from our house, but were in a "wind trough" due to topography which made that advantageous and working within cost constraints at that time (2012). The second pair of turbines was installed in 2019 with a more ideal siting. This permits the second pair to generate approximately 500 kWh more per year than the first pair. Also keep in mind, turbines are mechanical devices with moving parts which means they will need repairs from time to time. If you install turbines, you want to make sure it is done by someone who will be available to service and support them for ~20 years otherwise you may end up with very expensive "lawn ornaments."
We included wind turbines in our system because we needed to generate most of our electricity during the coldest months, which also have the shortest daylight, and work within a constraint of being smaller than 25 rated kW to comply with Wyoming's Net Metering Law, and NOT become a small scale utility with all the cost burdens that would entail. This is also why we have trackers for our solar PV arrays. We also have experience with both from our prior off-grid home since the 1980's. While I don't have a specific recommendation for who could do the installation and support for any renewable energy projects in your area, I have uploaded a PDF showing the conceptual diagram of how our system is laid out.
The
Skystream 3.7 Turbine was made by
South West Windpower which went out of business in 2013 after more than 20 years. It was bought out by Xzeres which has since been bought out by
HCI Energy in 2018. We "lucked out". Our installer,
WYCO Wind and Solar has continued to service and support our turbines despite all of these upheavals. As far as I know they are the only ones really doing that. They have created a niche business supporting what for most people is now an "orphan product." HCI Energy, as far as I know, is selling the turbines only are part of a combined wind and solar industrial site package. I don't know if what they offer would be usable for any homeowner. You can check with them directly. I've put hyperlinks in this reply which at the time I write this are all functioning, but may not in the future. You can contact WYCO and see if they know of anyone else in your area who works with wind turbines or see if they would do work in your area, but I suspect it would be very expensive to have them come from Cheyenne, WY to do work in Santa Rosa, CA. You can also look into other turbines. We picked and have stuck with the Skystream 3.7 because it is very low maintenance and withstands Wyoming winds, thus far on our property of gusts up to 90 mph with sustained winds of over 60 mph. Most other residential scale wind turbines fail under those conditions. When considering any turbine, look at their history of reliability. While many of the manufacturers of residential scale wind turbines no longer exist, the articles and reviews in the now defunct
Home Power Magazine which are accessible for free online through their archive, remain very useful and I recommend reading them. You might consider learning about the
Bergey turbines, which are one time were considered to be among the best made, but don't come cheap. You could also consider finding a
Jacobs Wind Electric which is what we had for our off grid home in Chadron, NE until 2012 when it was lost to a forest fire. Ours was originally built in 1948 and rebuilt by
Mick Sagrillo in the 1990's. Here's a
video link which you may find useful.
While I appreciate the sense of having plenty of wind to harvest power from, if I were where you are, before pursuing wind, I would see whether or not I could meet my electricity generation needs fully with solar PV. It's costs have decreased while residential scale wind power has increased, PV needs very little maintenance, which wind turbines can be reliable, they remain mechanical devices with moving parts, so will likely need more repairs than PV. Also, it is much easier to find service and support for PV which by its very nature is "modular" compared to wind turbines which really become manufacturer specific installations. This is why we have a "spare" complete turbine and multiple spare components (alternator, inverter board, etc.) for our system. We have these parts in case WYCO ever can't get them. Wind power, while important and appropriate for us, requires a substantial financial and knowledge commitment greater than solar PV, which is becoming ever more "plug and play." Someday, those differences may diminish, but for now they are the practical reality. This is why Tesla doesn't officially support wind power with its Powerwall 2 system even though as we demonstrated, it actually works very well with the Skystream 3.7 and might work well with other wind turbines. I hope this helps.