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Can this really be done? If you only run the toilets and kitchen sink to it. (think black water. We know what to do with grey water.) Could a composting toilet system keep up with a “normal household” load? These are a few of the questions I would like answers to.

Let’s try to answer the first question; Can this really be done? Not in my current neighborhood. But if I were to live in a more rural setting then, yes it could easily be done. The most major consideration is that the main unit be located below everything else. If one was thinking about a large slab foundation, this would be a problem. One would almost certainly have to have a basement.

Question number two; could a composting toilet system keep up with a “normal household” load. We will take normal to mean a household with 4 people. The real question becomes; how much water enters the system per day. For kitchen use we will say twenty gallons. For toilet use, we will say 55 gallons. That equals about 30 toilet flushes with a regular toilet. Low-flush or composting specific toilets would be less. For now, I will just use this number. From the information that I been reading, no. The system would have to evaporate almost 80 gallons of water a day. That is just too much.That said all the central systems have an over flow outlet. This could work but I believe you would always be overflowing.

If you used the SeaLand Toilet, you would reduce the 55 gallons down to a little under 2 gallon. That is because the SeaLand only uses one pint of water to flush the toilet. I think a the system could handle 22 gallons. But if we were to remove the kitchen waste water it would work as intended. The problem is that the kitchen waste water can have a large amount of food debris. This would not be a good idea to introduce into a gray water system. It could be done, but you would have to drain the sludge out much more frequently.

Third question; What about local building codes? If I was an inspector I would like this system better than a septic system. You are not burying anything in the ground! I am sure many people have had no problem with the inspector.

Lastly, cost. Does this thing cost more? No, in many cases it should cost much less than a septic and leach field. How much? I don’t know. But the top of the line unit sells for a little over $2000. + $500 per SeaLand Toilet¬† Having priced septic tanks for my rain water collection investigation, a 1000 gallon tank costs $1000. Then you have to deliver it. Then you have to dig a big hole for it. All that and you still need a leach field. Ever had to have your septic system repaired$$$.

Yes, if I were to build a home away from a local sewer system I would have a composting central toilet system and a gray water system. I would not want to bother with a septic tank or a leach field.


I have planned for a long time to reuse my old gas water heater and make a solar batch heater with it. Now, I am not going to use this for house hold water. No, much simpler then that. I am going to use it to heat my kids small swimming pool. So far I have spent $10 in fittings. I plan on spending maybe $5 more on black paint. Then I am done.

Here is a picture of the bare tank sitting on the back patio. I still have to sand off the foam bits and paint it.

I guess if I was crazy enough I could set it on some bricks and light a fire under it. It was a gas-fired water heater.

The system has a total of five misters. I get a consistent drop of 250 Watts while the misting is on. Personally, I think I could use some more misting. I think if I had pieced it together myself I would have better results. But, I had this going in less than an hour. That includes hooking up the solenoid valve to the thermostat contractor.

What does this all mean? During a hot day when the AC seems to run forever, we will use 10 hours, I save 2.5 kW hours. Having only run the system for a couple of days, I would guess an average saving of around 1.5 kW hours. That average over 150 days, 225kW hours per season. Maybe $25. This is the reason I wanted to be able to re-purpose the misting system. I will replace the AC unit before the misting system is payed for. But, I think of this project more as research then savings. I wanted to prove to myself that misting my AC unit does in fact save electricity.

How much water does it use? I don’t have any idea. I am sure not very much. This is why I think I need more misters. If one mister used 0.5 GPH. The system total would be 2.5 GPH. From the ten-hour example above, 25 Gallons per day to save 2.5kW hours. In Indiana it takes 0.41 gallons of water to make 1 kW hour of power production. This equals 1 gallon of water. So I am not conserving water, only electrical power. Water is a lot cheaper than electricity. Water = 6 cents, Electricity¬† = 25 cents

The usage for last month on only the AC compressor unit outside was 638 kW hours. This does not include the inside blower fan. I have calculated that I need to add about 12% more to the total to account for the blower. That would bring the total to 715 kW hours. The total for the entire house was 1334 kW hours. Air Conditioning accounts for over half of my total usage! I am sure that I am not alone. It was a hot month, last month. Every month Duke provides a chart for comparison. Every month it looks like this.

I am always to the far left of the chart. This makes me feel somewhat better. The misting equipment is on its way. After I install this I hope to reduce usage by 20%. We already know misting works, but will it cause harm to the outside unit? Since it is an older unit anyway I am not too concerned. I just don’t like to replace things when I am forced to. Do I think it will cause the unit to explode? NO. Do I think I may have mineral build up? Possible. That is why I am filtering down to 1 micron.

Total boring to watch but you can see when I start to mist the AC unit the Kw hours go down. This TED is only hooked up to the AC unit. Nothing else.
It is almost 100 degrees outside, heat index is 110. (Humid!!!)
Starts at 2810 Watts, goes down to 2450 Watts.
I am sure it would have been even better if it was less humid.

With this, I have ordered a kit. It is made by EZ misters. I know I could have made my own. But, if and when I replace my outside unit. I will not be misting it. With the kit I can re-purpose the misting. A big plus is that the kit is made for up to 200 psi. Since city water pressure is almost 100+ psi, I should get some great misting! (Small droplet size)