Any way to manage peak rates for dual fuel Infinity?

11 years ago

So I am changing to a peak electric rate system - details are somewhat complicated. The off peak rate is 5 cents, the on peak is only 7 but there is a demand charge for highest kW used during the month during peak. This demand charge will be the majority of my bill. Raleigh, NC. 2012 was $1200 electric, $150 NG total for the year. 2013 will be closer to $250 for NG since I upped the changeover temp and it was a cold winter.

The financial motive is use the heat pump during off peak down to 30 and the NG on peak ($.95 a therm). Peak is 6am -10 am and 1p-9p. The other motive would be to heat the house a little hotter from 10a-1p since electric is so cheap and the ambient temp is usually reasonable.

I currently use 45 degrees as my changeover.

The Infinity system is 2009 vintage.

Does anyone have a way to automatically do what I want? And if not - why haven't the HVAC companies come up with a way to deal with these peak rates?

As an aside, I would also like to tap into the utility saver modes for a/c but there is a lot of conflicting info out there. It seems to be based on software version and how things are set up. I would love to shut off the a/c when the dryer was on for instance. I switch next month and I will get a demand report - so it will be easier to figure out how to cut it once I can see what is going on.

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Comments (8)

mike_home
11 years ago
David,

I wish I had your problems. You peak electric rate is 10 cents cheaper than my every hour rate!

I have the same Infinity controller as you do. As far as I know there is no way to program heat pump and furnace lock at temperatures as a function of time. It is an interesting feature. There is no reason why the software could not be modified to support it. I think the HVAC companies have not yet started to think about peak rate usage. I could see the programming could become complicated and perhaps this is a reason why so far it has not been implemented.
Elmer J Fudd
11 years ago
David, I think you're doing pretty well. Try 30 cents per kwh for usage > 350 per month. It's easy to have mid winter and mid summer utility bills in my mild climate location that rival places with much more extreme temps.
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david_cary
Original Author
11 years ago
I am certainly not complaining but why not be even better?
weedmeister
11 years ago
I was going to recommend pre-cooling until I saw you have two peaks during the day. Pre-cooling is a concept where you run the AC in the morning for a few hours to bring the temp down to something like 70F, then turn off the unit for the rest of the day (or set the temp up to 78F). But since you have a peak rate from 6am to 10am which would be bad. I suppose you could try from 10-11am. And a simple programmable thermostat should be able to do that.

Heating is a different problem. I don't know if home control systems have been created to do this yet but I know they have been talking about it. (Control4, Energate, etc).
david_cary
Original Author
11 years ago
A/C is easy and I will precool the house - the summer peak is 10a-9p. It is the heating that is complicated - I have an ELK system and love to tinker but taking over the gas/heat pump control from Infinity is not going to be easy.
energy_rater_la
11 years ago
maybe countryboymo could provide you some
answers. he is pretty up on things utility related.

best of luck.
snoringcow
11 years ago
In the interest of keeping things simple, have to think it through - but it seems like finding a way to integrate a timer to switch from ODT to an IDTS at peak times would work. Just a thought.
ionized_gw
11 years ago
My first thought was that your best bet is to find someone that is retiring a system that runs a smallish commercial/industrial building and cobble something together from that. Even if you could figure out how to make it work, you might need factory support that would cost you more than you'd save.

Any way to manage peak rates for dual fuel Infinity?

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mike_home

Elmer J Fudd

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Any way to manage peak rates for dual fuel Infinity?

Comments (8)

mike_home

Elmer J Fudd

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