Call your electricity company. They pop the variables into their computer and out comes a monthly dollar amount. They did it for me for a new appliance recently.

Much cheaper to eat storage crops.

I'm paying $0.17 per Kwh, that's a 1000 watts for one hr costs 17 cents. If you have 16 40 watt bulbs that's 16x40 = 640 watts = 0.64 Kw. Then convert to kilo watt hrs: 0.64 Kw x 12 hrs per day = 7.68 Kwh per day. 7.68 x $0.17 = $1.31 per day.

I heat and cool a 1700 sq ft greenhouse for about that much. But then again the greenhouse cost about $25,000. I do grow about 2000 lbs of fruit per yr.

The Fruitnut

2000 lbs, Fruitnut, and you only started 4 years ago? That's pretty good, seems to me.

What kinds of fruit trees can you grow outdoors in your climate? And what microclimates could be created with permaculture.....

And how warm do you keep your greenhouse? And did you make it or buy it? What is it made of? Is it very well insulated?

Thanks for the help.

keepitlow: I hope you've learned what you wanted to know because it sounds like I've hijacked your thread.

I heat my greenhouse only enough to keep the citrus from freezing, 33F. I grow citrus, grapes, apricots, nectarines, plums, pluots, figs, and sweet cherry. This is my 5th crop and the production has been heavy from yr one as I planted trees already bearing age. Quality has been superb, the best I've ever eaten. I can pick something at peak quality every day of the yr.

I'm in Alpine Texas at 4500 ft elevation and have ideal weather for this project. About 60/30F in winter and 90/64F in summer. I have a chilling period of about 60 days in Nov and Dec. The growing season is the other 10 months with highs in 80s and 90s. Nights are ambient or 33F. The climate is modeled after the San Joaquin valley of California.

I bought the greenhouse. It has a double poly roof and is not very well insulated. But with an ave low near freezing and only heating to 33F, heating doesn't cost much. In a cold climate other options(like a three month dormant period in mid winter where you would only heat to the critical plant temperature for that stage of growth, so for three months only keep above zero)for fruit would make heating costs still reasonable.

The Fruitnut

keepitlow, fluorescent lights are only really strong enough to grow seedlings and cut-and-come-again greens (and low-light plants like African violets). They provide the equivalent of filtered shade down to about 8" from the bulb. There are other, more powerful kinds of grow lights that some people use to grow peppers and even tomatoes indoors, but it's very tricky: temperature, fresh air, watering, humidity, insect control, pollination are not the no-brainers they can be outdoors.

Check out the Growing Under Lights forum for more info and advice. Indoor Gardening Supplies is a good source of basic equipment. Start small.