On the breezier days, you would be using your windmill and storing your wind energy. Some power companies buy back power that you are not using. If using both forms of energy gives you more than what you are using, you could sell back the extra and use that money towards costs associated with your two forms of energy such as maintenance fees.
There are many pros to using wind and solar energy. Both types of renewable energy have a very small carbon footprint. They are a completely free source of energy and are found in abundance. They both require some modern technology to help harness them, and at one time the technology was unaffordable for the average person, but those costs are coming down in price and are becoming more affordable for home use. This is enabling them to compete in the market against the other types of energy. Expanding on wind and solar power instead of fossil fuels avoids the wildlife and human health impact of other types of energy such as fossil fuel burning, coal mining, and even gas and oil drilling and fracing. Windmills built bring in profit to a landowner. Land must be leased from the landowner and royalties can possibly be paid as a percentage of what power is being made and sold. Wind farms built in an area can bring in a boost to the economy by way of increased taxes paid to the area and workers who stay and eat in the area. Unfortunately there are also some cons to harvesting wind and solar energy. The weather isn't always ideal. Using the two energies intermittently helps when the weather wants to be uncooperative. If you have a small property area, you may not have the space for the solar panels. They are coming down in size, but depending on how much energy you need to harvest, you may not be able to have a large enough solar panel on your property. Solar panels cannot run 24 hours a day. When there is no sunshine, they are not productive. Windmills are not silent.
