Another Summer Update

Gosh, it's been so long since I did this I almost couldn't remember how to sign into this thing.

Thought I would throw out some more information on utility bills, etc.

First of all, to say it's been hot is one thing, we are almost 700 degree cooling days ahead of schedule for the summer and year.  One degree day is when the temperature is different from the normal thermostat set point for the whole day.  So if you average out those 700 degree days, that's something like 6 degrees hotter per day for the ENTIRE last 3 months.  One week we had 106 high for an entire week. 

That's not the worst news, though, it has not rained in that time either.  We have had a few sprinkles, and even a rain shower back in May, but just enough to get the ground wet.  The hazards are tremendous, but the fire hazard alone is dangerous.  Also worried about the trees lack of water.  Somehow, the weeds grow anyway despite the dirt being so dry.

Just this week, I broke down and started just putting a hose on some of the trees and dripping water to them for a few hours each.  Most of you would question why I didn't do this earlier, but the reason is that our trees are really picky about everything.  Just stare at them wrong and they will die.  The water here has a lot of sodium in it, and it gets plugged into the clay soils and the trees don't like it.  Our last neighborhood was pretty crowded with houses, and everybody installed lots of grass, which required water, and the trees all died.  The trees in question are Post Oak trees. 

OK, for our June electric bill................  drum roll..................  $133.90

I was shocked, in a good way.  For the several months up to this the HVAC didn't run much, and our bills were in this range.  June was hot, though, and the unit ran a LOT more. 

Some of you will want to qualify that with kWh, so here is that info...

1452 KWH used, at some mysterious ever changing rate somewhere around 9.22 cents.  The reason I say that is because the rates changed to summer rates some time in June, and now our rates are getting hit again for some building project somewhere. 

I don't have the July bill yet, but will any day now.

OH, this is interesting.  My loop temps have been steadily climbing.  I bought some electronic thermometers and hooked them up to all kinds of things.  My original ground temps were running about 72 degrees, but they are up to high 80's and low 90's now.  A lot higher than I thought they would be, but again, we are tremendously ahead of schedule for heat, and the ground can only dissipate that heat so fast.  The loop temps will climb during the day about 5 degrees, but tend to cool off at night again, indicating that the heat is dissipating out from the loop field, or underground water is sufficient to carry that heat away.  So, I called my HVAC guy and had a discussion about maximum loop temps, and the implications... Obviously, lower loop temps in summer and higher in winter is better.  Surprisingly, 130 degrees is the highest that will work with the unit, and he was surprised I was still under 100 degrees compared to his other clients. 

Also did some research with my friend Google, and discovered some technical papers on that issue.  From those, they were claiming about $1/degree/ton/month higher bill for temperature rise.  So if I am say 5 degrees ahead of schedule, for a 1 month period and running 3 tons, that's about 15 dollars more.  I was questioning one of our big decisions for install, which was to use another loop for a total of 6 loops, but we decided against it, thinking we had plenty of capacity.  I'm not entirely sure now, but wish I would have stuck another in the ground when it was easy.  BUT, so far everything is working great, and you can be sure that I will reap rewards from that heat this winter, and get some of that extra expense back, so on paper it would be hard to justify another loop in my case, even though it would have made me feel better. 

For the record, I would love to hear ideas as to how to get those loop temps down anyway.  Short of adding an in line cooling tower, the only thing I can think of is to put a soaker hose over the trenches that hold the feed lines to the loops, since they are most likely dried out from our lack of rain.  I'm even letting the kids take long showers to help dissipate heat out of the desuperheater, which does seem to help.  But the solar brings the temps back up in the solar and main tanks in a half day easy and I am back to hot tanks.  I wouldn't complain if it was winter, for sure. 

Now for those of you that may get carried away with all the technical advantages of GEO or high SEER units, please remember that the vast majority of our savings come from...

1.  Insulation (ICF exterior walls and open cell foam insulation with a "sealed" attic design)
2.  House placement (shading of windows)
3.  Windows  Low E 3 in our case, without a metal frame (vinyl, wood, or fiberglass)
4.  Tile roof
5.  Solar hot water (not a huge one but it helps)
6.  Lighting control system that minimizes light use when possible. 
7.  Reasonable thermostat set points... In our case 76 to 78 degrees depending on zone.
8.  Humidity control though proper sizing of HVAC system and minimizing air leaks and lots of thermal mass




I am blabbering again....



Hope this finds all well...