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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.

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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)

I heard of this a while back but never really gave it much thought until today. I gave my AC a lot of thoughts today because at 2:30am I woke up and the AC was not working. Me being me, I figure out what was wrong. At exact 12:35am, the run/start capacitor decided to stop working. (Thank you TED 5000.) I searched the Internet for a replacement. I can buy them, but not on Saturday. Plan B was to call the guy down the street in the morning that runs his own HVAC business. $100 later my AC works like it should.

That brings me to watering my AC. I noticed it was a little dirty. So I got the hose. But before I got the hose I looked at my TED 1000 attached to just the AC circuit. Before I brushed out the fins, 2770 Watts. After brushing, 2730 Watts. A small difference of 40 watts. Then I hosed it off really well. After hosing, 2330 Watts! That is 400 Watts! Almost 20%! WOW!

There are products on the market that do just this. Cool-n-save. The problem after looking into it is, mineral build-up. But that all depends on your water quality. At a cost of $100 I think I could make something better. Maybe I will do just that? I could possibly use the 24VAC from the thermostat, already at the AC unit. Just maybe?

I can’t let it simmer. I mean on some days I use almost 30 kW hours extra just to cool my home! And I only live in Indiana. Think of the people that live further south and want to keep their house cool.

My AC unit is almost ten years old. I think I can make a great case to replace it before it breaks down. Knock on wood, we have had no problems with it at all! It’s just very inefficient. Currently, I am thinking about an inverter unit. This brand also has a zone feature. Since I think the upstairs needs far more AC then the entire house it may save me money just because of the zone feature.

Next step is to get some quotes.

I have the unit currently on water heat duty. I use only 20 kW hours a month of the little 20 gallon hot water heater. Now I would like to get some good data for just the AC unit. One small problem is that the furnace fan will not be included on the TED 1000 display. I think I can just calculate the additional wattage and add it to the final number without too much of a problem.

Since my new electric bill just came out I have to wait almost two month to compare with the electric company. That does not stop me from comparing to the TED 5000 I have installed on the main house panel though. As I figured from before I would guess a new unit could save about 200 kW hours of a current 500kW hour AC load. Now I get to see if I really have a 500 kW hour a month load. šŸ™‚

Cool your house with ice generated at night! That is right. Mostly right anyway.Ā  Ice Energy has a produce that “makes” ice at night and uses the stored energy during the heat of the day. So for all you people out there that have TOU rate plans, this could save you money. (I am thinking of California!)

Basically, you have a regular AC unit that runs at night to make the ice inside the unit. When the thermostat calls for cold air, the ice is then melted providing the building with up to 30 ton-hours of cooling. (360,000 BTUs) I will use my house as an example. The other day it was 90 degrees outside. My air condition ran most of the day. Lets say 12 hours. I have a 2.5 ton unit. That would be about 2.5 x 12 hours = 30 ton hours. (convenient) If I was in California and had TOU (Time of Use) like most do, I may have paid $0.40 a kWhr. (3kW x 12hours x $0.40 = $14.40 a day) With the Ice Bear 30 that I run at night… (3.5kW x 10hours x $0.10 = $3.50 a night) That is a savings of $9 a day. A few things to note. One the regular AC unit is running in the heat of the day this will cause it to use more energy. On the flip side the Ice Bear is running in the cool of the night. This will cause it to use less energy. Even though the Ice Bear has a 4.3 ton compressor. It could use less energy because of the temperature difference between night ad day. In this example the AC would have never run out of ice until the end of the day. Everything is good. But if the ice did run out then the Ice Bear would have turned on it compressor and started to cool the building. Thus never leaving you without air conditioning.

On a similar train of thought. Think if you had a solar system installed. You would be selling power at peak rates and then buying it back during the cheapest times, middle of the night. This Ice Bear system could actually allow you to install a smaller solar system because of the rate differences. By the way, most power companies love it when you shift your load to an off peak time. Why? because they have excess capacity at night and not enough in the middle of the day. That is what TOU is all about. They want you to change how and when you use electricity. By making it cost more when they can’t generate enough.

Again, this technology is not for me. I have a flat rate structure. I also want a heat pump. This would mean I would have an Ice Bear and a heat pump and that would not make financial sense at all. It will work with heat pump. All they do is place a dedicated heat exchanger in the air handlers air stream. Everything works the same but you can run the heat pump in heating mode.

So, for some of you out there this can save you some serious money! Especially, if you already have solar on your roof.

If I have a backup style grid-tie solar system will my inverter start my Air Conditioner? Maybe, just depends on the Air Conditioners LRA rating and the inverter starting capacity. LRA means Locked Rotor Amperage. This is the inrush current that any motorĀ  has when it first starts up. The motor in this case is the compressor.

Here is an example that may e similar to many installations. (This would be what I am thinking of doing in my house anyway.)

Inverter would be a Xantrex XW 6048. It has a LRA surge rating of 52.5 amps. My current air conditioner, I think, is a 2.5 ton AC unit. Since I don’t know the LRA rating I used a new Goodman SEER 13 unit. This unit has a LRA rating of 49 amps.

Yes, the inverter would start the Air Conditioner. Or would it. Remember there are two other fans in a split system. A condenser fan and a blower fan. Both of these have a LRA ratings also. So in the end the chance of starting the entire system is low. Especially since you will have other power users running while the Air Conditioner is trying to turn on.

So I can’t run the entireĀ  house AC unit on the inverter. But can I run a small window unit. Yes, if the unit is 120V this inverter will not have a problem with it. That is because the inverter has a surge rating of 110 amps @ 120V. The house air conditioner was @ 240V.

If you wanted to run a window unit with an off the shelf inverter take the amperage while running and multiple by 7 to estimate the LRA draw. So if the running amps is 5. Then the estimated LRA would be 35 amps. Take the 35 amps x 120V = 4200 Watts. This would be the minimum size surge rating inverter you should buy.

Inverter-Driven Rotary Air Conditioners.

The nice thing about this type of air conditioner is the running amperage is very close to the Locked Rotor Amperage. The inverter in the AC unit starts the compressor out slowly and then ramps up to the desired speed. This means that if your windows unit or your central unit has this newer technology many more DC toACĀ  inverters will do the job. The Xantrex XW line of inverter should have no issues getting it done. (FWIW – when I upgrade my AC I would like to go with an inverter type heat pump.)

So you have an older AC unit. You live in the south where you run the air all the time. You are a perfect candidate for a Heat Recovery Unit.

What is it you ask? It is an add-on device that works with your Heat pump or air conditioner to make hot water. It uses the hot compressed refrigerate to do it. Instead of blasting the hot temperatures intoĀ  the atmosphere, itĀ  puts it into the water.

Trevor-Martin Corporation makes a heat recovery unit. (They also make add-on heat pumps)

You can read the benefits for yourself but I would like to post just one thing,

I heard that Heat Recovery Units will decrease the efficiency of my air conditioning system. Is this true?
Absolutely not!! As a rule of thumb, a Heat Recovery Unite will increase your A/C efficiency by 10%. It also reduces the head pressure on the compressor; thereby reducing stress and improving compressor service life.
You get three benefits from adding a heat recovery: Free hot water for your house; reduced air conditioning cost; and improved A/C operating life.

Sounds very good to me. Since I don’t run the air for more then six months a year it does not make me a great candidate for it. But, if you do have a large cooling load, think of a restaurant or gas station with a car wash, your hot water would be… for the most part… free.

I have had my new Air Vent installed for a few days now. Nice cool air for a few hours in the early afternoon. Installation was very easy. Total time was about 1 hour and 30 minutes. I had to install a “Street Elbow” to make room for the Air Vent because originally the expansion tank was in the way. I only had to shut the water off and screw it in.

Air Vent Installed onto the Air Tap

Air Vent Installed onto the Air Tap

My only complain is that they should have made it the same color white as the Air Tap. But it is in the basement and I did not buy in because it looks pretty. I am still trying to quantify the savings the Air Tap will have on my electric bill from the cooled air waste product. If the unit runs for 5 hours a day. That would be a net increase of 35,000 BTU of cooling into the house. That is the same as runing my AC for well over an hour. Maybe now that I have the cooled air directed to somewhere useful I will see an impact.

Here is a three day chart of the last few days.

ACThreeDay

In case you can’t read the little data tags on the bottom; the high bars are during the day and the low bars are at night. Air Conditioning is the “problem”. I am just one house. Imagine all the other houses that have air conditioning. Each one is adding at least 4 kW of extra demand on the power company. Power companies don’t build power plants to meet this demand. They build “Peaking Plants” These plants usually are Natural Gas and cost much more to operate then Coal Power plants. They are cleaner but they are costing you more money. I am not saying you should turn off your air. People can die from excessive heat. I just want everyone to know what is happening. Right now I am using 4.54 kW of electrcity. It is costing me $0.32 an hour to use at that amount, and I am generating 7 lbs of CO2 per hour.

Side note: TED is a great tool to help determine the size of a backup system. Fossil fuel or solar. If you notice, I demanded only 5kW at my highest peak. Granted this was averaged over an hour but you can get data for every second of the day if you wanted too. I am thinking about the generator systems sold at th big box stores. Generac comes to mind. Here is a link to there sizer. Heat Pump, Electric Range, Microwave, Freezer, Sump Pump are the options I select. What does it come back with. 17kW – 22kW generator. Since I have had my TED installed I have NEVER been about 10kW, and if I was above 7kW it was for maybe 5 minutes at most. So I would only get the 10kW unit. Maybe the 8kW unit if I left out the electric stove for the backup circuit panel.