EcoRenovator  

Go Back   EcoRenovator > Improvements > Geothermal & Heat Pumps
Advanced Search
 


Blog Register 60+ Home Energy Saving Tips Recent Posts Search Today's Posts Mark Forums Read


Reply
 
Thread Tools Display Modes
Old 01-05-14, 11:18 AM   #1
stevehull
Steve Hull
 
Join Date: Dec 2012
Location: hilly, tree covered Arcadia, OK USA
Posts: 829
Thanks: 241
Thanked 165 Times in 123 Posts
Default graphical analysis of GT heat pump

My electric utility has a data logger that gives graphs and data for daily electrical consumption and the average temperature for that interval.

I grabbed about two months of data and plotted average temp vs. kWhrs for each day. I have geothermal heat pumps in both houses and I expect that the colder it gets the more consumption

Not surprisingly, the above is true, but I was surprised at how linear the relationship was. To be truthful, I have used this analysis for other companies and homes and it works when you have a meter you can interrogate (or look at) on a consistent basis (natural gas meter for example).

For this, I looked up our local winter degree days and average winter temp. From that, I can find from the graph, the average daily kWhr consumption and the statistical length of winter.

By observing where the electrical consumption is at 65 F, I can account for basal use. Subtracting total from basal use, I can see just how much just heating costs.

Mind you, I must appear rather extravagant to many uses here, but this accounts for two homes, barn office, pumps for water (livestock) and heaters to keep livestock waterers from freezing.

Now I post and see if converting the Excel spreadsheet to a PDF and loading that helps. Thanks Daox!


Steve



Attached Thumbnails
Click image for larger version

Name:	chart.jpg
Views:	687
Size:	117.7 KB
ID:	3841  
Attached Files
File Type: pdf average daily temp vs. daily kWhr.pdf (201.9 KB, 349 views)
__________________
consulting on geothermal heating/cooling & rational energy use since 1990

Last edited by Daox; 01-06-14 at 09:18 AM..
stevehull is offline   Reply With Quote
The Following User Says Thank You to stevehull For This Useful Post:
Daox (01-06-14)
Old 01-05-14, 11:21 AM   #2
stevehull
Steve Hull
 
Join Date: Dec 2012
Location: hilly, tree covered Arcadia, OK USA
Posts: 829
Thanks: 241
Thanked 165 Times in 123 Posts
Default

Rats, doesn't look too good as the spreadsheet got spread over several PDF pages. But hopefully, you get the idea and the utility.

The regression line also allows you to calculate the average R value of the homes. You need to know total surface area.

Steve
__________________
consulting on geothermal heating/cooling & rational energy use since 1990
stevehull is offline   Reply With Quote
Old 01-06-14, 09:19 AM   #3
Daox
Administrator
 
Daox's Avatar
 
Join Date: Aug 2008
Location: Germantown, WI
Posts: 5,467
Thanks: 1,110
Thanked 367 Times in 298 Posts
Default

I was able to paste the images together for you.

That is some interesting data. Thanks for sharing.
__________________
Current project -
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.



To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
&
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Daox is offline   Reply With Quote
Old 01-06-14, 10:34 AM   #4
pinballlooking
Super Moderator
 
pinballlooking's Avatar
 
Join Date: Jun 2013
Location: SC
Posts: 2,791
Thanks: 164
Thanked 533 Times in 437 Posts
Default

Nice data you are a great candidate for solar power.
Maybe some help here?
USDA Rural Development-BCP_ReapEaReda

http://www.rurdev.usda.gov/BCP_ReapR...Financing.html

Last edited by pinballlooking; 01-06-14 at 10:37 AM..
pinballlooking is offline   Reply With Quote
Old 01-06-14, 10:58 AM   #5
stevehull
Steve Hull
 
Join Date: Dec 2012
Location: hilly, tree covered Arcadia, OK USA
Posts: 829
Thanks: 241
Thanked 165 Times in 123 Posts
Default

Pinball,

I have already done an analysis on my site (using PVwatts), have gotten quotes and it looks like I can get a system for about $1.70 a watt for a 10 kW system (self install).

Need those before I apply to USDA or NRCS.

I do a lot of summer irrigation and that eats up a lot of kWatts.

The purpose of the graph is that I can predict, rather accurately, my winter heating costs. From the graph, it looks like two houses and barn office costs me about $432 a year for heating.

Geothermal heat pumps are a simple no brainer for return on investment. Even more so if you rig one up.

Steve
__________________
consulting on geothermal heating/cooling & rational energy use since 1990
stevehull is offline   Reply With Quote
Old 01-11-14, 01:12 AM   #6
ecomodded
Supreme EcoRenovator
 
Join Date: Sep 2012
Location: Vancouver Island,Canada.
Posts: 1,036
Thanks: 116
Thanked 100 Times in 87 Posts
Default

your heating system runs amazingly cheap Steve, Im impressed you can heat all that for 450 a year, I pay 1,000 a year to heat 1 house.
I am currently pricing HP's to find the best mini split for heating almost exclusively.
I seen a few that provide more heating btu's then cooling btu's .
ecomodded is offline   Reply With Quote
Old 01-11-14, 10:53 AM   #7
stevehull
Steve Hull
 
Join Date: Dec 2012
Location: hilly, tree covered Arcadia, OK USA
Posts: 829
Thanks: 241
Thanked 165 Times in 123 Posts
Default

Eco,

The heating season cost of $450 is due to a number of factors - one being our low winter kWhr rate. That said, minimizing air infiltration, extensive use of efficient lighting, high R/low E windows, use of home thermal mass "flywheel", insulation, outside deciduous tree placement all make the low total number of winter kWrs dedicated for heating.

My local coop electric utility gives a $750 rebate per ton for a GT heat pump and the state association of rural electric coops asked some of us with GT heat pumps to document our electric use so they could figure out just how good GT heat pumps are. Instead of sending in the model numbers of refrigerator, dishwasher, dryer, I did the above performance analysis.

They just didn't believe my numbers! They insisted that I must be burning wood. Sadly their engineer was not astute enough to be able to interpret the graph. So I offered to go to a meeting and them "walked" them through the graphical analysis. Once they understood, they were amazed at just how efficient these units are - and just how good they are for a utility. They are now considering offering low cost loans for GT pump installation (instead of ton rebates) as the lowering of monthly electric cost is so large that it will quickly offset purchase/installation and amortization costs.

I could burn wood as a major energy source (lots of wood here), but I choose not to. The costs of a GT heat pump are just SO low that I find it incredible that people do not use (or build their own) technology.

But there are drawbacks . . . Recall that I do use a water well and there are only so many cycles on that pump - and then you get a new one for ~$2000. So that too must be figured in somewhere . . .

My particular situation uses a lot of summer irrigation for livestock (frankly mostly cooling them off in the sprinklers vs. watering pasture), so I am typical in using a lot of water for that. By pulling BTUs out of water in the winter, and storing the "waste" water in farm ponds, I can use that water volume later on. In the summer, the heat pump also uses water in the "pump and dump" situation to also refill the ponds. A fair amount of water in those ponds sinks back into the aquifer and some is also lost to evaporation, but the majority is used or recycled into the aquifer.

Last summer, one major GT heat pump manufacturer did a "swap out your old for a new" promo. Several of the local dealers had very good working order heat pumps that were to be "disposed of". I helped them with that for some low cost housing and also allowed the local water utility plant to use them as a demo project for their offices. In both cases, the performance is so spectacular that they will use GT technology for further projects.

Contractors here are VERY conservative and many cannot comprehend how a GT heap pump can be 400-500% efficient. Air source heat pumps got a bad name some 15-20 years ago so they do what is simple - use conventional SEER 15 technology for cooling and burn natural or propane gas for heating.

One big problem I have is my basal use (daily ~ 50 kWhrs). This is more than many people on this site have for total daily use! I have multiple freezers for retail frozen beef, fans that run 24x7 in the summer (for livestock), home HVAC circulation fans that run 24x7, water pumps for livestock to drink from, barn office that must be conditioned as I keep drugs and heat/cold sensitive supplies in there, use of the heat recovery ventilator, etc., etc.

I heat water, cook and dry clothes with propane and get "free" hot water in the spring/summer/fall from the GT heat pump desuperheaters. Have thought about reinstalling my (in storage) flat plate how water collectors, but they really won't help too much considering I must run them with electricity (drain back pump system)..

Installation of 10 kW of PV panels is the answer as we have abundant sunshine many days of the year. This will reduce my total consumption by about 50-60% (from PVWatts). But gears turn slowly with NRCS and the USDA in terms of loans/grants. I do see a further reduction is cost per kW of PV power in 2014, but nowhere hear what has happened in the last years. But I must act soon . . .

GT heat pumps are not for everyone. Where there is extensive underground hard rock, lack of a suitable aquifer - they are just impractical. But the vast majority of us live in areas where GT heat pumps work with incredible and sustainable (ecologically speaking) performance.

Recall my friend in the mountains of Colorado where we kludged up the summer AC using water from an uphill cold spring, a radiator and a fan? He is now thinking of using that water for a GT heat pump. By law he cannot divert the spring water for any consumption use (does not have water use rights), but he can simply divert some of the BTUs and then return 100% of the water to the natural riparian flow.

Did not mean to go on and on . . . .



Steve
__________________
consulting on geothermal heating/cooling & rational energy use since 1990
stevehull is offline   Reply With Quote
Old 01-11-14, 03:07 PM   #8
ecomodded
Supreme EcoRenovator
 
Join Date: Sep 2012
Location: Vancouver Island,Canada.
Posts: 1,036
Thanks: 116
Thanked 100 Times in 87 Posts
Default

I see your not in a cold climate , that explains your heating costs. With solar you will be set, all your lighting and pumps and fans could be set on a small thousand watt solar battery bank.

I am unsure how much energy your GS heat pump uses but it would be nice to have a PV set up just for it to run independently.

Your 10,000 watt system would make revenue plus be a steady supply to draw off with little need for a large battery bank. I feel having more on tap power would be simpler cheaper require much less oversight and is more Eco friendly.
excess juice could be used to heat water for Btu storage or as was brought up just sold back to the Company since your not off grid.

You certainly have the land for your Ground Source HP , what a perfect set up , with your ponds and all. Good Job


Last edited by ecomodded; 01-11-14 at 03:09 PM..
ecomodded is offline   Reply With Quote
Reply


Tags
graphical analysis, heat pump

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 02:33 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
Ad Management by RedTyger
Inactive Reminders By Icora Web Design