PV Gap

Juan Said:

how do you compare natural gas, burning wood, and solar energy as home-heating methods.?

We Answered:

I built a passive solar house that provides about 80 percent of its heating and about 30 percent of its cooling needs for free. It cost nothing more to build it this way than it would have cost to build it stupidly. Another 50 percent of the cooling cost is electric, for exhaust fans and small pumps that circulate cold water through tubing in the floor slab.

We only use air conditioners in the very hottest weather, and run the heat in the very coldest weather. We have a wood cookstove in the kitchen that has a water jacket around the firebox and can heat the whole house by circulating the hot water through the tubing in the floor slab. We only use the gas water heater for heating when we need extra heat and are not using the wood stove for cooking.

We also have solar photovoltaic panels, batteries, and inverter that provide power for the cooling fans and pumps. The solar panels to run electric air conditioners and other heavy loads were too expensive, so we use power from the grid when it is really, really hot, and also to wash clothes, run the TIG welder and shop tools, and a couple of other heavy load items.

We use propane for domestic hot water, a small range in the kitchen, and a gas dryer.

The whole thing is not as complex as it sounds, but requires more thought than most houses require. And it can approach zero operating cost when conditions are ideal.

To answer your question: we still have firewood left from clearing the driveway, so it costs "nothing." If we had to buy firewood, it would be the most expensive form. It also has a big environmental footprint, because of the barf gasses in the exhaust. Always plan on a catalytic converter. The equipment cost for efficient use of wood heat is very high. That catalytic cookstove with water jacket cost over $3200 installed.

Gas is cheap right now, and has both the highest heat content and the sweetest exhaust. It costs horrors and death to produce, but if we don't buy any, other people will. So the horror is a well-distributed responsibility. An efficient passive solar house with gas backup heat, hot water, and dryer is the most efficient overall approach. I use wood chiefly because I like the look and feel of the fire. Use it a lot less than I expected to, actually.

Well, that turned into more of a ramble than a scientific exposition, but it will give you some idea of the complexity of the factors and their interaction. In real life, it turns out to depend more on day-to-day sensing and judgment.

A dum-bass republican in the neighborhood told me I was being unpatriotic because I was not consuming enough petroleum products. So there are many costs. What do you do?

Johnny Said:

Solar Bird Bath - how can I make one at home?

We Answered:

Not a good idea to have warm water for birds to bathe in, it strips all of their natural oils from their feathers, which can result in skin problems.

You don't have to heat it up for them, how do you think they have survived all these years in the cold weather? They don't mind, I wouldn't worry about heating it up for them, a normal bird bath should do just fine.

Good Luck :)

-------edit--------

Who wants to drink warm water? It doesn't matter why you put it out, they will still bathe in it if it is there, they don't know what's good for them.

If you are going to make one, however, make sure the water is more cold than it is warm, that should be ok for them, but I would still urge you not to, I know you care, but they really don't need it.