No more water heater woes!

No more ~5kW instantaneous jumps means the water heater is finally running correctly

So, my water heater woes appear to have finally ceased.  Last Friday, the GE repair guys (thanks Jeremy!) showed up and dismantled my Geospring to remove and recharge the refrigerant.  A new error code had appeared (F1) when I opened up the crawl space before their arrival.

From what Jeremy (GE repair tech) explained, there was a chance that the amount of refrigerant was either too much or too little in my unit when they had repaired it last.  Of course, it could also mean that there is a refrigerant leak within the compressor which CANNOT be fixed.  Only time will tell on that one which means I'll be watching this system closely.   But it's nice to see the system working correctly now.  Per the pic above from our usual AM shower activities, notice how there isn't a large jump in the power usage to indicate the electric elements turning on.  For reference, below is an older pic showing the large jumps.  

Before the fix. Notice the large jumps in power usage indicated the water heater elements turning on.

 


 

  

UPDATE: Water Heater Woes Continued...

Temperature in the Crawl Space from last night: next to the Geospring and the crawl space door (Bottom Value=56.1F)

Continuing on from my current discussion, so I'm been watching the Geospring to see if Friday's fix of the control board has worked.  Well, my skepticism has been right.  This AM, I checked the TED5000 and it appears the Geospring is still not operating correctly.  And I know its got nothing to do with the temperature in the crawl space because that's fine...and this AM it was  a nice 47F outside while the crawl space was at least 56F.  The graphs below show the AM routine with showers and such.  You can easily see the electric elements on the water heater turning on (a healthy ~5kW) 3 times over this morning for showers.  The 3rd time is when my wife cleaned the dishes in the sink.

Morning Energy Consumption.  The first big jump and 10-min plateau is the water heater running for my wife's shower.  The second is my my shower (with the 'thorn' on top for my wife's  hair dryer).  The third...well, I'm not sure.  Laundry?

Below is a closeup of the 3rd jump.  What I find a little odd is the "noise" on the graph (the jumping up/down).  That's kind of unusual.  Just look at the data before and notice that the data is very smooth.  And after is a little "rough" also.  Thinking about this...that's got to be the clothes washer.  I'm guessing it must be that little bit of "juice" to keep the drum moving.  Neat, huh?

Closeup of the 3rd turn on of the water heater electric elements.  

Since I can't zoom or change the scale on these graphs, I downloaded the raw data from TED and opened it up in Excel to graph.  The results are below so you can easily see the "noise" from the clothes washer.

Excel Plot of the clothes washer "Noise"  Lots of ups and downs.  

Anyhow, regardless of what the clothes washer is doing, I'm still a little peeved about my water heater still not operating correctly.  It should be running the heat pump exclusively.

Reminder of the weather station next to the water heater with the water heater set to "Heat Pump Only"

Well, I guess I'll get the *joy* of calling GE again and hopefully this time I won't get the rude person who's trying to tell me I'm wrong and I don't understand how the water heater works...along with the threat that I'll have to pay for the service "when they find there's nothing wrong".   If I'm wrong, I'll gladly blog about it and apologize.  Until that happens...which it hasn't to date...

Water Heater Woes Continues...

OK...so recall a little while ago (cue the Scooby-Doo music and squiggly lines), I was having some issues with my GE Geospring Heat Pump Water Heater.  Well on Friday last week, the back-ordered control board finally arrive and week later (yesterday), the GE repair guys showed up and installed it.  As a fun note, the water heater was showing the dreaded "FC/F14" (failed compressor) error when I opened up the crawl space before the guys arrived.

Well, go figure, today I'm getting ready to feed the dog while my wife was showering and I noticed on the energy monitor that the energy usage was sky-high.  Well, what the heck!  I checked and the downstairs heat was on...OK...that's about 2.5 kW (Stage 2).  The upstairs heat was not on.  And then while looking around I heard her hair dryer come on...that's about 1.5kW.  So I checked TED and this is what I saw the following:

Morning Power Usage.  The ~2.5kW is the heat.  The final blip is a hair dryer.  The big jump is the water heater.

 Huh...there' a huge roughly 5kW jump...so the electric element is on the water heater again!  WTH?!?  Didn't those guys fix that yesterday?!?

Well, at this point I can't do any more investigation because I needed to cook breakfast for the family. In case you're wondering, it was waffles.  And yes, they were awesome.

So after cooking and cleaning up I checked on the water heater.  While doing dishes, I did run over to the corner of the house and listen and I could hear the heat pump working.  Well that's good!

After I had finished cleaning, everything I checked the power monitor and *$%&$%, the electric heating element was on again!  Well, now I was free to check on everything.  Below is my series of pictures where I made sure everything was off.  There was no heat on, upstairs or downstairs.  The dryer wasn't running.  We weren't cooking or baking.  And nothing else was running (fridge, freezer, kegerator).  I also checked the temperature in the crawl space...and it was a healthy 59F.

TED5000 showing my energy usage

Temperatures.  Upper is Indoor.  Lower is Crawl Space.  Ignore the time, I've never set it.

Downstairs heat is not running.

Upstairs heat is not running either

Geospring showing it in Heat Pump Only Mode.

While down in the crawl space checking the water heater and taking the above picture you could hear the a click which I'm guessing was the electric elements turning off.  I verified it with the below pictures...

Yup, all heating (air and water) is off. 

Below is the TED screenshot.  You can see the event described earlier (~6:30am) with the hair dryer peak.  And then there's cooking breakfast followed by doing the dishes.  Then everything turns off while we eat followed by the final water heater peak when I was doing this investigation.

TED5000 energy monitor

So I'm going to try an experiment.  I relocated my weather monitor right next to the Geospring.  Not to say it was much further away...maybe 10-15-ft, but now it's only about 1-ft away.  And it is also right next to the crawl space door.  This should be the coldest it should ever read, if for some reason, air is getting through the insulated and weatherstripped door.  It happens, so I'm trying to give it the benefit of the doubt although one would think that if it were significant enough, I'd see huge fluctuation in the temperature in my entire crawl space...which I do not see.

Geospring with the weather (temp/humidity) monitor now located beside the water heater.  The door is about 3-ft away.

Looking at the monitor now, it is showing a lower temperature...53F instead of 59F.  Then again, I did just have the crawl space door open while I went inside to grab the weather station, then move it over and position it (it didn't want to stand up so I had to put it on its side), and then take the picture.  And even with that, it's still nearly 8F higher than the minimum temp.  So I'm overly surprised that the temperature it lower. 

Either way, I'm going leave this here for a while to see if the temperature drops to below the 45F threshold where it overrides the heat pump and goes to electric.  I *highly* doubt this is the case, but I can at least rule it out.  I'll keep y'all posted.  Otherwise, I guess I'll have to call GE repair again to get them over to figure out why this thing keeps running the electric heat. 

Water Heater Woes

Go figure, as soon as it gets cold, then issues arise.  Recall that i have one of those fancy GE Geospring water heaters that use a low energy heat pump to heat my hot water.  To date, it's worked nearly flawlessly with the only hiccup being a Thanksgiving when I had so much family in the house, that my water heater couldn't keep up with demand in the "heat pump only" mode that I have my unit set on.  So I just changed the mode to be "hybrid" to allow the electric elements to kick-on and produce the extra hot water necessary for ~6 showers in the morning.  

My GE Geospring water heater in my crawl space

Well, all was great until just after Thanksgiving when I noticed I had a lot of energy usage.  Trying to troubleshoot led me down to the crawl space where I found a "FC" error code on the GeoSpring.  Thanks to the "Google", I found this this meant "Failed Compressor" and (apparently) it's not an unusual occurance via comments and blogs.  I went ahead and called GE customer service and scheduled an appointment for after the Holidays (I was traveling).  They mailed the parts to me ahead of time which included a bunch of new parts.  

On Monday, the guys arrived and they plugged in their laptop (when can I get one of those appliance communication modules?!?) and ran a test to verify that "Yup, the compressor is broken".  So they ripped out the old one and put in the new one while leaving me to scramble for PVC parts to reattached the drain piping.

Old Evaporator.  There's a surprising amount of rust here for something that isn't even 2 years old!

Pic i used to go to Lowe's where I picked up a union and a nipple to reattached the drain piping

So after they put everything back together, it appeared that everything was working.  The fan was running which indicated that the compressor was running producing hot water. 

Well, funny thing, the next day I was getting ready to feed the dog when I glanced over at the energy monitor and saw it using 6 kW.  Wow...that's a lot!  So I searched around the house.  Drying not running; upstairs heat off; downstairs heat off; Oven off...huh.  My wife was making some stuff in the toaster oven, but that's rinky-dink...only 1.5kW.  So I set off to the crawl space to check on the water heater.  Suspicious, I flipped the breaker and guess what?  The electric demand instantly dropped...bullseye!   Below is a screenshot of the power usage via the TED5000 and my phone.

Real-Time Energy Usage showing the water heater on...then off at the sudden drop.  And the pick-up when I flipped the breaker back on.

Once I verified, I flipped the breaker again and you can see the water heater heat pump turn on as it goes through its start-up cycle.  Huh...so why was the electric running when I had the unit set to "heat pump only"?  No idea.  So I just assumed it was a minor blip...I made sure the temp was set right and it was still on "heat pump only", then closed up the crawl space and went on my merry way.

Well, the next morning, my wife wakes me up to say, "there's no hot water".  WTH?!?  So at 5:30am I trudged down to the crawl space again.  No error codes present.  So I changed the mode to "hybrid" to enable the electric heat.  As soon as I hit enter, you can immediately hear the electric units turn on and hum.  And the energy monitor verified that the electric heating was on with an instant 4.5 kW bump in usage.  This got me annoyed...why was the heat pump not turning on???  I closed up the crawl space and checked the temperature and even after the crawl space door was open when I was checking the water heater, the temperature still registered 63F..no where near the 45F limit.  

So I broke down and called GE again to get my unit serviced.  After the troubleshooting guy argued with me about the crawl space temperature (I monitor it...trust me, I know it stays between 60-65 all year round...coldest ever was 58F), I got an appointment with a stern warning that if they don't find anything wrong with the unit, they'll charge me.  Since then I got a call from one of the service guys who I talked through what I saw (very nice gentlemen) and they suspect it's the control board.  So that's been ordered...and actually its on back-order...with a tentative appointment to replace it on the 20th.  I'm really hoping that'll fix it. Luckily, this is all no-cost to me since it's well within its 10-year warranty.  

Today's energy usage on TED.  Maybe that step around 5-6am is for the water heater?  After 7am is the dryer.  At ~8pm (19:00) the previous day you can see the water heater come on for the kiddo bath-time usage

This AM, I did try to check to see if the electric water heating was on, but I can't see it on the graphing which is odd  (maybe it is hidden in there around that 4.5-5KW area before 7am?).  Granted I didn't get the opportunity to go to the crawl space and check.  There was plenty of hot water this AM which was nice given that it was a frosty 11F outside (20F colder than yesterday).  

Anyway, we'll see if and how this gets resolved. It's a little annoying that this is happening to a fairly new unit.   

October Energy Bill. Up yet still Down

September  2013 Energy Usage

Wow...what a wondrous month its been.  The kiddos are certainly keeping me busy and slightly sleep deprived.  But it's getting better.  Every week they are sleeping a little more during the night.   As I mentioned last month, I knew my energy usage was going to sky-rocket.  But I think it's been manageable.  While overall, my energy usage for this month compared to last is up by 45% (see detailed info below), I was expecting much worse.  Let's show the Bill results first:

October 2012 (Sept 5 - Oct 2) --> Blog Post Here

Total Energy Consumption = 409 kWh
No. of Days = 28
Average Daily Energy Consumption = 14.61 kWh/day
Bill = $49.91


October 2013 (Sept 4 - Oct 2)

Total Energy Consumption = 595 kWh
No. of Days = 28
Average Daily Energy Consumption = 21.25 kWh/day (45.5% INCREASE in consumption)
Bill = $68.13

Looks bad right?  However, October 2012 was also one of my lowest energy usage months ever too.  Much of my usage was in the first half of the month (see the Pic above) where I was using about 30 kWh/day.  That was all HVAC usage as I needed to keep the house around 72F for the kiddos.  Halfway through the month I was able to turn the system off because the nighttime temperatures were cool enough to allow me to open up the windows at night and use "super fan" to cool the house.  

So I asked myself...how does it compare to October 2011?  The geothermal was still installed, just not the GE Geospring.  So here's that comparison:

October 2011 (associated blog post here)

Total Energy Consumption = 771 kWh
No. of Days = 32
Average Daily Energy Consumption = 24.09 kWh/day
Bill = $79.75

So 2013 was a 11.8% DECREASE in energy consumption compared to 2011.  Now, there's some savings.
So in about a week, I'm getting 1.962 kW of solar panels installed.  I chose to go this route since I believe I've done what I can practically on the energy efficiency side of my home.  All that work resulted in roughly a 50% decrease in my annual energy consumption (compared to 2010 when I moved in) .  Only after all of that work was done would I consider energy generation.

Overall, the solar panels should produce roughly 1/3 of my annual power usage.  I have a limited southern roof exposure so that was part of it of not trying to get more.  I could always add more panels in the future, but they would have to go on my West Facing roof.  Stay tuned next week for that blog posting.  I'll also include my math on ROI.

Updated (Non-Official) HERs Rating

Unofficial HERs Index for my House

So the other day I was bored and came across my former HERs rating report completed last May.  The report showed my house had a rating of 71 which meant that it was ~55% more efficient than a typical existing home (HERs rating =130) and ~29% more efficient than a standard new home (HERs rating = 100).   Since I've done a whole bunch of projects since then (most notably the attic radiant barrier and the GE Geospring), I was curious what my new score would be.

So looking through the report, in the footer it noted that the report was completed using the "REM/Rate - Residential Energy Analysis and Rating Software v12.99".  Using Google, I input the information and found the website for the software.  As I hoped, they provided a download for the software.  So I downloaded v14.1.  It's a 90-day trial version that's full featured except I can't print anything.  That's fine by me...I'm just playing anyway.

Luckily, my previous energy auditor, AltruEnergy, had sent me the REM/Rate file for my house (*.blg).  This was great because it meant I didn't have to re-enter all the information from the report!  Time saver!  After opening the file and doing the all-important "Save-As", I verified that my previous HERs rating did not change (it didn't) and then I started updated.   I added the following:

• Added in R-5 to the foundation walls for the XPS I added this winter.
• Added in R-5 to the Rim and Band Joist via the XPS I added this winter (1^st floor only).
• Note:  I have not added ventilation to the crawl space yet.  I’m waiting for my spring tune-up.  At that time, my HVAC guy is going to install the new vent in the crawl space.  So I didn’t update that in the file.
• Added in Radiant Barrier to the ceiling (all except the small vaulted part in the bonus room) which I installed last fall.
• Updated water heater to be my GE Geospring (EF=2.4) which includes an extra R-10 blanket I added myself.   It also runs in series to maximize desuperheater production.
• Updated the geothermal system such that only 1 unit has a desuperheater (only the downstairs unit has one).
• Added in my new fridge.  I got one of those French door fridges.  Not only is it bigger than my old one, but it uses nearly half as much energy per year.
• I updated the dishwater information to reflect the actually kWh/yr via the Energy Guide.
•  I updated the dryer to have moisture sensing which it has.
• I updated the clothes washer with the actual information for my unit via the Energy Guide.
• I updated my lighting to be 100% CFL.  It’s really more like 80% CFL and 20% LED.  But there's no option for LED in the software.  My exterior and garage fixtures are all CFL also so I put those to be 100% compliant.
• I updated the ceiling fan CFM/watt to ~92 CFM/watt.  We have 5 ceiling fans in the house, all of which are energy star.  The old file said we only had 1.  I actually replaced the one in my master bedroom (which we use nearly every night in the summer) with one of those DC motor ceiling fans.  It uses 327 CFM/watt…which is about 3x better than other energy star ceiling fans!  It’s still on clearance at Home Depot online (Hampton Bay Winfield).

The results are below (it's also in the pic above if you were paying attention)...drum roll please....

Unofficial Home Energy Rating (HER) Certificate  Note:  The NO PRINT is because I'm using the trial version.

My unofficial revised HERs rating is a 54.  Sweetness!  So I'm nearly 50% more efficient that a new standard home.  And by energy star standards, my house is house is ~30% more efficient than a new standard home...assuming an energy star home is 30% more efficient than a standard home which would give it a HERs rating of 70.  In case you're wondering from the certificate above, I don't actually use $1,379/yr for energy.  I'm much below that ($1,091).  The above number is scaled for a family of 5.  There's only 2 of us now, although soon we'll be close with twins on the way.

Side note:  I'm not advocating that anybody else do this...I'm just an Engi-nerd that enjoys tinkering.  I did send my file back to my Auditor for a QA/QC check...so I will say these results are preliminary.  Although I'm not sure he'll say anything definitive just because he probably doesn't want to advocate for folks to use this software who don't know what they are doing.  Being a modeler myself, I understand that when it comes to models,  "junk in = junk out".  So if you don't know what you are doing, you could just producing useless numbers.

One of the nice things about having the software is that I can run some scenarios for projects that I was contemplating.  These include:

• Replacing the siding and including R-5 XPS insulation (continuous barrier)
• Replacing the windows with new Low-e, Argon filled windows
• Install Solar Panels

Replacing the siding and the windows is an expensive proposition.  The siding itself would be ~$15k while the windows would probably be another $10k. Well, the software essentially told me not to bother.  Adding in the extra R-5 on the outside walls only saved be $50/yr!  The windows were another $50.  Obviously, doing it for energy saving purposes does not make sense.  Maybe for the windows installing a window film would make more sense because its significantly cheaper and would reduce the solar heat gain in the summer and the heat loss in the winter.  The return on investment would be significantly better while providing a similar benefit, although definitely not as great.  But it would be a fraction of the cost...if you believe the websites it's 10% of the cost.  So $1k vs $10k.  That could be palatable for my wallet.

The only thing that did make sense was the solar panels....but I pretty much already knew that.  The panels lowered my HERs rating to a 43.  However, that's a $4-5k investment.

January 2013 Bill Results...Another Big Reduction

A pic of my dog enjoying his new Xmas chew toy.  Yes, those are my super awesome slippers.  They certainly help keep the cold floors away from my toes!

Hello folks-

The holidays have past and so has another year of energy savings.  My Duke Energy Bill was not quite like a Christmas gift (Hey Duke...a great gift would have been NO BILL...hint hint) with the results posted below:

January 2012 Bill
Power Usage:  1,318 kWh
No. of Days:  33
Average Daily Consumption:  39.94 kWh/day
Bill:  $121

January 2013 Bill (Dec 3 - Jan 3rd)
Power Usage:  940 kWh
No. of Days:  31
Average Daily Consumption:  30.32 kWh/day  (24.1% reduction from 2012)
Bill:   $95.84
Absolute Bill Savings:  $25.16
Rate Adjusted Savings ($0.102/kWh): $50.47

I gotta say...wow.  I never expected this...especially since last year we were fully into the Geothermal.  My power usage was the same as last month at 30.3 kWh/day...I'm consistent.  It does make me wonder...let's check the Heating Degree Days (HDD's) from NOAA:

Dec 3 - Jan 3 2012
No. of HDDs:  533

No. of Days:  33
Average Energy Usage:  39.94 kWh/day
Average kWh/HDD:  2.45 kWh/HDD

Dec 3 - January 2013
No. of HDDs:  538

No. of Days:  31 

Average Energy Usage:  30.32 kWh/d
Average kWh/HDD:  1.75 kWh/HDD (28.8% reduction from 2012)

So, there was just as many HDDs as last year...and actually its more given that there's 2 less days.  Yet I had less Energy consumption, so I guess some of my energy reduction projects are paying off.  Most likely the GE Geospring ASHP water heater is really helping given that its this time of year (Brrrr...cold) that a lot of hot water is being used.  But I'm sure some of my other projects are helping out too:

1)  HTPC Upgrade
2)  New Fridge
3)  Better Controlling Ecobee Thermostats  (My HVAC installer is now an authorized Ecobee Installer...He liked my setup so much he signed up!)

Below are some pics from my Ecobee Home IQ for the month:

Downstairs Ecobee Information

Upstairs Ecobee Information

I will say that this Ecobee information is pretty useless to me as is.  I'm got lots of questions for Ecobee.  Such as the stars...how can 1 part of my house be 1 star and the other be 3 stars?  Especially if both systems appear to run identical hours!  And I have the same house information for each thermostat!  And yes, my system runs 68% more than a typical system in my area (BTW...what is my area?)...it's a heat pump...it will always run longer than most conventional systems.  Not to mention it was sized correctly so it will always run longer (closer to optimum) which is its maximum efficiency.  Not to mention, if you're comparing my geothermal heat pump to a furnace, my system will always run longer.  My system doesn't blast out 120F air for 5 min then turn off.   If you notice my average house temp set point is 65F.  That's pretty awesome!  I could let it go less, but there's no reason to.  That's because my house never cools lower than this temp.  Check out the pic below from my Ecobee:

Upstairs HVAC runtime information via my Ecobee Thermostat

First off...let me say that the information above is what really makes the Ecobee spectacular. OK...if you look at the graph above you'll see that when my house cools my system just barely goes below 65F before its called to start heating to meet a "I'm home" set point.  It appears yesterday though that it had to turn on once for about 5-10 min...shame.  Overall, my system doesn't even turn on until it's needed...so a set point of 65F works.

My next project will be installing XPS insulation on my crawl space walls and the rim joists.   My downstairs wood floors are pretty dang cold and insulating the crawl space walls and rim joists should significantly help it...at least that's what people say.   I'm still a little skeptical given that I feel like insulating the floors themselves would be best...although i guess insulating at the source makes sense too. 

A side note to this...I used my handy Black and Decker  thermal leak detector to check out the temperatures in the crawl space.  On a 26F morning...I found that my brick walls which are exposed to the air were somewhere around 38-41F (some small corners registered at 32F!).  Very cold!  The walls that were not exposed (i.e. underground) were 50-55F...so 10-15F warmer.   The crawl space air itself was 59F.  So apparently if I insulate the walls, while letting in a little HVAC air (just a smidgen) I can keep the crawl space significantly warmer which will make my floors warmer.

That should be fun.  When I finally get around to it, I'll post a bunch of pics to show how I did it and hopefully include results...unless we have another freakishly warm January/February like last year.

New GE Geospring Hot Water Heater!

My new GE Geospring hot water heater in series with a preheat tank (not shown)

So I finally put in a new hot water heater.  As I had discussed in previous posts, I wanted a GE Geospring air source heat pump (ASHP) hot water heater.  Well, that's what I got.

Why am I so hyped about this?  Well for starters...

1)  The Geospring is rated at an energy factor of 2.5 which saves roughly 63% of the energy as compared to normal electric hot water heater (which I had).  On an annual average basis, my former HW tank was running 0.8 hrs/day @ 4.6 kW for 3.7 kWh/day.  Thus, this is expected to be reduce to 1.37 kWh/d.  

2) I had mentioned in some of a previous posts, that the geothermal supplemental hot water generator (desuperheater) really is not optimized when using one tank.  I'd read some forums that even claimed it could be costing me energy with calls for geothermal system manufacturers to remove the 1 tank setup from its installation procedures.   Well, this new hot water tank was connected in series with my "old" hot water tank (now un-powered).  The "old" tank will act like a preheat tank allowing for maximum hot water generation via the desuperheater.  This preheated water will feed the GE Geospring.  So overall, the energy required for hot water generation is cut substantially.

3) The Geospring is so efficient because its an ASHP hot water heater.  Essentially that means its an air conditioner connected to hot water heater.  So it will "condition" (remove heat and humidity) the air and instead of discharging the heat outside, it takes the heat and pumps it into the hot water tank.  Why does this benefit me?  Well, recall I've been using a dehumidifier in my crawl space to reduce moisture...and its been a fairly large energy consumer.  Well, the Geospring will now take the place of the dehumidifier by simultaneously conditioning the air (removing moisutre) as it heats the hot water.  Thus, I'll hopefully be able to negate using the dehumidifier entirely! That should save me somewhere around 7 kWh/day alone.

Overall, I'm hoping this work will reduce my overall power consumption by about 9.33 kWh/day.  It could be higher including optimization of the desuperheater, but I have not way to quantify this yet.  Even at 9.33 kWh/day this is about 280 kWh/month!  If you consider that in the last year (Sept 2011 - Sept 2012), I've averaged 853 kWh/month, then the 280 kWh/month will result in a roughly 33% reduction in consumption!  That equates to roughly $31/month.    This project cost me about $1200 to install, so that's a 3.19 ROI (not assuming any rate increases).  I'll take that... Only time will tell what I actually achieve...   

 

Hot Water Heater

So I've been trying to figure out what else I need to do to reduce my energy usage.  There's things like:

1) Install high efficiency hot water heater
2) Replace siding on the house and put on house wrap
3) Install solar panels
4) Replace fridge
5) etc.

Well...I don't have a ton of money to spend so #2 and #3 are automatically out as those cost multiple thousands of dollars...if not above $10k.  That leaves me with the fridge and HW heater.  Well...at most the fridge might cost me $60-70/yr.  And while I could get a bigger fridge that is more energy efficient...I'd still only save maybe $5-$10/yr.  Yeah...that's not worth it.  So that really leaves me with looking at the HW heater.  I checked out TED from the last 48 hrs and it looks like the HW heater runs roughly 7x/day for about 10 minutes.   The Geothermal system is not operating...it's that nice fall weather so I'm not heating or cooling.   That also means the desuperheater is not generating hot water.  At 4.8kW, that means the HW heater is using 5.6kWh/day.  And I'm currently using 22 kWh/d.  Thus, my HW is accounting for ~25% of my current total daily electricity usage.  Obviously that value will change with increased HVAC usage...but its the numbers I have now.

OK...so one of those hybrid hot water heaters (http://www.geappliances.com/heat-pump-hot-water-heater/ claims a 62% reduction in energy usage compared to a standard hot water heater.   I verified this by looking at that yellow tag energy information.  My current 50-gal HW heater says it'll cost me $520/year and 4879 kWh/year.  The hybrid says $198/yr and 1856 kWh/yr.  There's lots of assumptions included in there (family of 4, using XX gallons per day, $0.105/kWh, yadda yadda)...but let's assume that this is relative and be scalable to my usage. I can't see why it wouldn't since it's based on usage.

This would mean I could expect my energy usage to reudce from 5.6kWh/day to 2.1 kWh/d.  From a cost standpoint, that's $66/year in savings.  My return on investment:   $1000-$300 (tax rebate) = $700/$66 = 10.6 years.  Not a great return, but it's a return...and its within a 'lifetime'.  I should note that next year my electricity rates are going up 15%.  And Dook Energy is trying to raise them another 15% the following year.  Using just the one rate increases bring my savings up to $76/yr and make my ROI to 9.2 years.

One thing I should also note is that the hybrid HW heater is essentially an air source heat pump (ASHP) attached to a hot water heater.  So when it runs...it's essentially an air conditioner.  It's taking the heat from the air and transferring it to the hot water.  That means my crawl space (where my HW heater is located) will become 'conditioned'.  So no more dehumidifier needed (that's an extra 3 kWh/d minimum which isn't included here).  So that's cool.

However, I'm a little worried if there's enough 'heat' down in the crawl space during the winter.  I know last winter, the crawl space hung around 68F...and I had crappy vents in there.  I know i probably had duct leakage...but it wasn't too signficant as I had the energy audit guys down there and I fixed the places that had bad leakage.  I was reading online and some folks saw the unit drop temperatures down to 45-47F in their basements....which required them to drop a duct to give it some heat. 

So I'm thinking what I'll do this winter is I'll insulated the door to he crawl space and then monitor the temperature in the crawl space to see what happens.  If temperatures stay fairly warm, maybe I'll swap out the hot water heater...

Any thoughts out there?  

UPDATE:  Now there's always switching to gas to save moeny.  But that's not cheap either.  First, my hot water heater is in my crawl space.  And I'd need to vent the exhaust....which I doubt I have space for.  So for a standard gas hot water heater, I'd probably have to move it someplace else (garage?)...and I'd need an electrician and plumber for that.  And that isn't cheap.  I could go tankless and gas.  Again I'd need to move things around...and that unit is ~$1500.  And a 7.4 gpm unit ("2 uses") would still cost $223/mo @ 1.22/therm (using the Energy Guide).  So its still not better than the hybrid uni...not to mention it'll be more expensive to purchase and install.

UPDATE 2:  I just found this in the WaterFurnace Desuperheater User manual.  Apparently, it's more efficient to install two HWs in series to allow the first one to be a preheat tank to maximize the desuperheater usage.  I'll definitely have to think about this...