Global Sun Solar Oven - up to 400 degrees for less than 300 dollars

Solar Cooking has come a long way. 
During the sun hours of the day, the food is cooked in the same amount of time as a regular oven. And it has become the preferred way of cooking lots of meals because of how it cooks the food. Solar cooking allows many of the natural flavors of food, which get baked out in conventional ovens, to remain. The slow, even rise in temperatures in a Global Sun Oven gives the complex carbohydrates time to break down into simple sugars allowing subtle natural flavors to emerge. Sun baked foods stay moist, the natural internal juices do not bake out, resulting in a superior, moist taste and much less shrinkage. 

• Cooks Any Kind of Food with the Power of the Sun - No Fuel Needed!
• Reaches Temperatures of 360 to 400 Degrees Fahrenheit!
• Totally Safe - No Danger of Fire!
• Used Daily in 126 Countries Around the World! Ruggedly Built
• As Portable as a Small Suitcase! 22 pounds
• Dimensions: 9 in x 12 in. With the shallowest point from the glass at 5 in.

Solar energy prices, roughl estimate

Learning to live on and off the grid is a question of economics and solar position. 

This is a good article on your initial planning steps. 

It does not factor in the current rebates offered by local andnational governments. 

The size of your system and battery bank will depend on how much sun your location receives (sola insolation) and how many consecutive days overcast conditions may keep your system from producing energy. More than likely, you will want to add a backup engine-generator to your system rather than having to size your battery bank to meet the worst-case scenario. A generator will also help you maintain the health of your battery bank, safeguarding a large part of your investment.

Here is a basic idea on what to factor in for using solar. 

System Type 2 kW 5 kW 10 kw

(small/average) (average/big) gigantic

Off-grid $20,800 $52,000 $104,000

Grid-intertied $16,000 $40,000 $80,000

This does not include passive solar systems which heat up the water so that the water heater does not have to work so hard. These systems are known as integral Passive Solar Water Heaters. 

This is a cheap solar cabin that provides the basic electricity with some great pictures on how to rig a simple solar electrical system with a generator. The apparent cost was less than 3,000 dollars. This will be able to provide Light, Computer power, charges, small appliances but not heavy amp users. 

Read more about this inspired cabin setup here.