I'm offgrid and both electricity and heating for my small energy efficient house is provided by PV solar. The lower cost for heating with PV is thanks to low cost PV solar panels with cost amortization well under 2 cent/kWh over the life time and even lower cost and simple thermal mass storage. My total system cost in USD is around $15000 and this is DIY so no labor was included. Everything except the small $2000 LiFePO4 battery should last 30+ years while battery may need replacement in 20 years based on 0.9% degradation per year observed. That means $15000/ 30 years / 12 month = $42/month for both heating and electricity about half of that for each. And to be even more detailed I use 5000 to 6000kWh/year for heating and about 1440kWh/month as electricity (average 120kWh/month) So $21 / 120kWh = $0.175/kWh for electricity and just ($21 x 12 ) / 6000kWh = $0.042 for heating (less than natural gas). My open source solution can be fund succinctly described on my Kickstarter page [url=https://www.kickstarter.com/projects/electrodacus/solar-bms-and-digital-mppt-for-pv-electricty-and-h]Link[/url] The user manual for both DMPPT and SBMS contain the HW and SW files linked in the last page. The house is in Saskatchewan Canada so not a warm climate below is a photo from today overcast and fogy still the PV array produced close to 4kWh more than enough for electricity needs most of that was electric cooking. Thermal mass storage is large enough to deal with up to a week of such bad weather. [img]http://electrodacus.com/DMPPT450/P1260149.JPG[/img]

I suggest you look at sunamp heat store if you got that much pv --you won,t need a hot water tank then either and in most homes dhw is biggest expense when house in low energy type.
this is the way we are going inUK now --vritually no heat loss from it when it is charged up compared to well insulated thermal store https://www.sunamp.com/

https://forum.buildhub.org.uk/topic/5167-ashp-sunamp-no-boiler-no-pv/