The problem is storing the energy to generate heat overnight. LaCasaVerde has one solution. There are others ways to store heat directly.
Other thoughts would be candles, a kerosene lamp or heater or even a tiny wood or charcoal stove using trimmings from your trees although you may need to rig a thermostatically controlled blower to keep the temperature in a good range.
As for solar electricity, as with all methods, you need to figure the energy you will need. I will assume that a 100w incandescent light bulb would fit your needs. If you burn it for 12 hours you will consume 1.2 kWh of energy, equivalent to 100Ah at 12 volts. That determines the battery you will need. It needs to be double the energy you will us - in this case 200 Ah - at a cost of around $600 for an appropriate deep cycle battery. Solar panels run around $1 per watt. If you get 10 hours of usable sun per day, you need a minimum of 120 watts. With losses and cloudy days you should at least double that. A 250 W panel would cost you $250. A 20 amp charge controller runs around $100 and a 300 W inverter to produce the 110 volts for the light bulb would run under $50. That is about $1000. The battery is the limiting piece here (other than usable sun) and is also the most expensive.
Prices are from Northern Arizona Wind and Sun (https://www.solar-electric.com
) which also has an awesome online forum with many real experts to answer any solar power questions you may have.