In this case it included only one of two vehicles and only part of the heat as we use wood as well. The impact of vehicles depends on where they are during the

In this case it included only one of two vehicles and only part of the heat as we use wood as well. The impact of vehicles depends on where they are during the day. If they're at home you can put in more solar without more batteries as you'll just charge them directly. For winter heat the panel orientation is important so the winter drop isn't as severe when the sun is low. If you want 100% electric winter heat then sizing the array for that and having excess power in summer shouldn't be that much of a penalty as the battery is what is expensive and winter heat doesn't require any more of it. You'll just end up gifting the power company more power during the summer time, which will help with the electric load of all the air conditioning. Investing in insulation and a heat pump may be better though.