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.

Ecobee Thermostats Installed!

Ecobee Thermostat Installed on my wall

I finally bit the bullet and bought the Ecobee Smart thermostats.  They were $260 each which wasn't too bad.  Installation was a little bit of a hassle. It was difficult because the instructions were not clear for my geothermal installation.  To me, it was not clear what Power went where. Below is a pic of the former Honeywell thermostat.

Pic of the wiring from the former Honeywell Prestige IAQ Thermostat

 Luckily, the Ecobee support team was great. I emailed them and they were very prompt in their response. We went back and forth a couple times (thank you Gus!) and eventually we found out that I only have 1 @ 24V power supply while the diagrams listed two supplies.  So I needed to run a jumper wire from one 24V input to the Ecobee to the other side of the control board.

Ecobee Control Module Installation.  I did clean the wiring up more after the pic was taken.

Once that was determined, it was a breeze.  The upstairs unit includes the flood sensor (the thick red wires on the bottom left in the above picture).  If the flood sensor registers a flood it will shut down the air handler AND will send me an email.  Pretty cool, huh?

Final Installation of the upstairs Ecobee Control Module.

Programming the Ecobee was very easy.  For the most part I kept the default settings that were recommended by Ecobee for a geothermal install (that was a menu option in the Installer Setup).  The only things I changed were the delta for when the system turns on/off and the Stage timing.  For the delta, I set it to be 1.5F instead of 1F.  For this I'm just sacrificing a little bit of comfort for more energy savings.  For the Stage timing, I set Stage 1 to run for a max of 2 hrs before Stage 2 turns on.  Stage 2 will run for 3 hrs before it calls for the emergency electric heat.  Thus, my system would have to run for 5 straight hours before it will call for the expensive, inefficient heat.  In addition, the system will stay on the most efficient stage as long as possible.

The web interface is pretty cool.  A pic of it is below.  I can pretty much change any setting I want from the portal.  And its generally much easier to do it here than on the thermostat.  Below is a pic of the thermostat settings.  The dark blue is "sleep", orange is "awake", green is "away", and light blue is "home".  So for Monday-Friday, the vast majority of the time is "away".  Then on weekends, I have more "sleep" and "home" time.

Ecobee Web Portal

 The only cool thing is that I can check out graphs on how my systems are operating.  I can see the setpoints, the indoor and outdoor temperatures, humidity and the system run time.  It's very cool.  The Ecobee site also produces monthly runtime reports and lets me know how my system is doing compared to other homes of a similar size and geographical location.  Since I've only had it installed for +/- a week I'll have to wait to show y'all the results of the report. 

Downstairs Themostat Operational Information

Upstairs Thermostat Operational Information

 The Operational data is all downloadable.  What would  be VERY COOL would be if I could link this system data with my TED5000 home energy usage data.  This would allow me to track exactly my energy usage from HVAC.  That's probably a task for someone smarter than I.

There's also a Android App that I use on my phone.  It essentially lets me change the temperature, turn the system on/off, check the weather or set a vacation schedule.  Below is a screenshot from the phone. I can easily switch between thermostats too.

Screenshot from Ecobee Android App

 What would be really cool would be if I could look at the Operational information from the App.  Right now the only way to to do it is to login to the website from my phone.  It's a little bit of a pain...but not too bad.

Optimize Geothermal with new Thermostat?

So I've mentioned this before in previous posts, but I'm not too happy with my Honeywell Prestige HD thermostat.  It's pretty looking, yes.  But for being a $300 thermostat, it's control options are not all that great. 



Honeywell Prestige HD Thermostat

One of things that I'm most unhappy about is the inability to control how the unit calls for Stage 1 and Stage 2.  Why is this important to me?  Well, Stage 1 is more efficient than Stage 2.  And it seems whenever I walk by the thermostat, the unit is registering that Stage 2 is running. 

Let's take a closer look....

In Cooling mode, Stage 1 has an EER (Energy Efficiency Rating) of 26.8 while Stage 2 is 18.6.  So Stage 1 is 44% MORE EFFICIENT than Stage 2. (FYI..in terms of SEER, Stage 1 should be about a 31 and Stage 2 is 21).  However, Stage 2 has a greater capacity:  27,200 BTUh vs 21,500 BTUh.  So Stage 1 would have to run 1 hour and 15.9 minutes to achieve the same heat transfer as Stage 2 in 1 hour.  However, even if you factor in the longer run time, Stage 1 is still 31% more efficient than Stage 2.  So it's definitely beneficial to run Stage 1.  This assumes that the desuperheater benefit is the negligible, which in reality probably factors Stage 1 (longer run times means closer to steady state operation and higher heat transfer efficiencies).   And longer run times and means less Start and Stops on the compressor which is beneficial to maintenance. 

Now let's look Heating.  This benefit is no where near as great.  Stage 1 has a COP (coefficient of Performance) of 4.7 while Stage 2 is 4.2.  This translates to a HSPF (Heating Seasonal Performance Factor) of 16.05 for Stage 1 and 14.34 for Stage 2, so Stage 1 is about 12% more efficient,  Stage 1 has a heat transfer rating of 16,200 BTUh while Stage 2 is 19,500 BTUh. So Stage 1 would have to run 12 minutes longer to achieve the same heating as Stage 2.  Inclduing the extra run time, Stage 1 is still 10.6% more efficient.  Now, if I assume the desuperheater is running scalping 5% of Stage 1 (it automatically turns off for Stage 2), then the savings plummets to 5.9%.  But it's still a savings, albiet small. 

So what does this mean in terms of dollars? I create the following table below using the 2011 Cooling Bills.  The savings do not include the last 7% increase in Duke Energy rates for this summer.

2011 Summer Cooling Bills:
	Energy	Days	kWh/d	Bill	Rev Bill	Savings
06/01/11	1086	33	32.91	103.14	71.58	31.56
07/01/11	888	28	31.71	86.97	60.36	26.61
08/01/11	941	31	30.35	90.65	62.91	27.74
09/01/11	771	32	24.09	79.75	55.35	18.30	(Red by 25%)
					total	104.21	per year
2011 Winter Heating Bills:
	Energy	Days	kWh/d	Bill	Rev Bill	Savings
11/01/11	963	30	32.10	92	86.54	5.46
12/01/11	1318	33	39.94	121	113.82	7.18
01/01/12	1075	29	37.07	103.18	97.06	6.12
02/01/12	1051	29	36.24	107.9	101.50	6.40
					total	25.17	per year
			Estimated Total Annual Savings	129.37	per year

So during the 2011 summer months, there's a chance for about $100 in savings.  During the winter...not a lot at only $25.  I could roughly double the winter savings if I disabled the desuperheater in the winter.  Overall...even at $125/year that's not bad at all.  A HUGE decrease...no...but still measureable.



Ecobee Smart Thermostat.  It also has web-enable features too.

 So how can I fix this?  Well, I was looking at the Ecobee Smart thermostat.  This thermostat would allow me to set Upstage timers such that the system will stay in Stage 1 as long as possible as long as it doesn't violate any rules (such as...the temperature continues to rise or drop by X degreesd during operation or the timer doesn't "time out' before reaching the goal temperature). 
If I go with the Smart thermostat, then it could cost me about $600 ($300/thermostat).  Being conservative, the ROI would be about 5 years.  If I were to go with the Smart's new cousin...the Smart Si (not nearly as cool as the Smart, slighly harder to install, etc)...then the ROI would be 3 years as the thermostats only cost about $200 each.  I could also do one of each too. 

And all of that is before I talk about the really cool (nerdy) features such as reports that track the inside temperature, your setpoint, and the systsem run time.  And it's web-enabled so I can control it from anywhere (my wife will not be happy about that)

What do y'all think?  The downside is that my thermostats are brand new...however that could be a blessing because I could probably sell them to offset the cost of the new one. 

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...

September Duke Energy Bill

Yes folks, yet another month has passed and I was waiting at the mailbox eager with anticipation...for a bill.  This month's electric bill came in and showed continued fantastic results:

Electricity Usage:  941 kWh
Days:  31
Avg Usage:  30.3 kWh/day
Comparing versus 2010:  37% savings (aka reduction in energy usage)
Comparing versus townhome of less than half this houses area (2009):  6% higher.

I'm thrilled.  It appears that we've had a consistent ~40% reduciton in energy usage.  And, I'm using about the same amount of total energy as if I were still in my former townhome.  Just sweet!

I would expect the savinsg to be more if I can figure out where the humidity is coming from in my crawl space.  I have the dehumidifier running 6 hrs on/6 hrs off.  During that time, the humidity drops to 45% when on...then raises to about 55-60% when off.  I'm not sure but it might be hitting the 45% humidity mark and turning off.  I need to check the manual to figure this out.  UPDATE:  Yes, I verified this and once it hits around 45% (the setting on the unit is 50%), it turns off....and then restarts again when the humidity increases. 

UPDATE on TED:  Energy Inc (the MFRs of the TED unit) sent me a new display.  Well, that one didn't work...it wouldn't connect to my gateway.  After discussions with tech support, apparently they sent me the wrong model (there is a series 21 and a series 20...I have a series 20).  That should arrive today.  It'll be nice to have the ole' TED display around again...

UPDATE 2:  FYI, my TED unit had 993 kWh for the month vs the 941 for Duke Energy.  That's a ~5% error difference.  I think the # of days was the same...but I think TED is setup to record from the 2nd to the 2nd, while Duke Energy this month went from the 6th to the 6th. 

UPDATE 3:  Well, the TED display arrived and this time it showed it was picking up a wireless signal, but again, it was not showing the data.  Hrmmph!  We'll see Tech support says this time.  I have a feeling it's a firmware issue.

UPDATE 4:  FYI...I have no idea why my August post is in front of my September post.  Maybe once I update this post it'll move it ahead...maybe...I hope... 

UPDATE 5:  I finally fixed that August post...someone is double-posted...so I just deleted it.  So very odd...

August Energy Bill in...

I've never been so excited to get a bill in.  Our Duke Energy bill showed up this afternoon while I was mowing the lawn.  When I wife let me know I immediately asked, "How much?!?!"  When she mumbled something to the range of 2600 kWh, I replied, "No F*$&#ing way!"  That's when I went inside to find she was way off.  Note...she did admit that she has no idea where that number came from since there isn't any 2600 or 2xxx number on the bill.

Anyhow...the totals (drum roll please...):

Total kWh = 888
Days = 28
Avg = 31.71 kWh/d
Aug 2010 Avg = 51.13 kWh/d (over 32 days)

2011 Savings = 37.97%  Boooyahhhh!!!

Cost for July/August (trying to get an equivalent # of days):
2010 (54 days) = 2586 kWh = 47.89 kWh/d -->$246
2011 (61 days) = 1974 kWh = 32.36 kWh/d -->$190
Savings = 612 kWh -->$56 ....and that's using 7 days more electricity!

OK...compared to our 2005 built townhome:
2009 Total Energy Usage:  34.24 kWh/d
2011 Total Energy Usage:  31.71 kWh/d
Difference (2011 vs 2009):  92.6%

So again our work has paid off!  Our 2700sf home built in 1986 used 7.4% less energy than our 1300sf townhome built in 2005.

That's just awesome!  Again the savings would be greater if I wasn't running the dehumidifier so much.  But, how can I complain???

I will note that my TED unit estimated 1071 kWh were used for the month.  My first thoughts was that its a fairly big error although we were 3 days short (28 vs 31 days).  3 days @ 31.71 kWh/d = 95.13 kWh+888 = 983.13 kWh.  983.13/888 = 10.7% error.  I guess you can't complain about a 10% error for a residential product.

Energy/Cost Savings...What to do next?

Ok...I Friday and yesterday I spent countless hours trying to get my HTPC to shutdown and wakeup automatically.  When I manually told it to turn on in 5 minutes and shut it down manually, it worked fine, turning on automatically.  When I let it automatically turn off, it did just fine, but then it wouldn't turn back on.  It appears that I just can't get the system to pass the correct date/time in there.  Not sure why...Long story short...I'm fed up with it.  I'm no linux computer expert and I spent most of my time on Google trying to figure out commands.  I know enough to get by, but that's it.

So, I thought the next most logical step was to finally start looking at an upgrade to reduce power usage since this is on 24/7.  Well...a question arose...are there better investments?  Let's take a look...

I measured all my HTPC components with a Killawatt meter and the total usage is 120W when idle.  The computer itself uses 92W.  Reading online, a nice Intel Core i3 system (with all the accessories) uses around 40W when idle.  So that would save me 52W.  On a daily basis thats 1.2kWh which would save me $0.106/day = $3.23/mo = $38.72/yr.  Generally I would invest about $300 into this which gives me a simple return on investment (ROI) of 7.75 years.  Not all that great, right?

Well...looking at my TED, it's pretty obvious the one thing that is using the most power in my home is the hot water heater (see large single spikes).  The graph above shows last weeks worth of hourly energy usage.  The block on the first day (Sunday) is from doing laundry so that's a mix of hot water and dryer usage.  Overall, It's that time of the year when I don't need heating or cooling, so my geothermal is turned off (House stays between 67 and 75...comfy!).  With the system off, my desuperheater isn't heating my hot water.  So...does it make sense to upgrade my hot water heater?

Well, one of those GE hybrid hot water systems costs about $1400 from Lowe's (I'm not including the tax credit because I can't buy it this year).  If my current hot water heater (4.8kW) is on, say for 2 hrs/day (only 1 hr shown above, but let's factor in winter), then that I'd use 9.6kWh/d which is $0.82/day = $24.8/mo = $298/yr.  A hybrid hot water heater (according to the website) would save me 62%.  So, without factoring in the desuperheater, my ROI is 7.6 years.  With the desuperheater reducing hot water by 40% (a conservative value) then the ROI rises to 12.64 years.  Overall, I'd say this fix isn't worth it unless my hot water heater decides to break.

Out of curiosity, how about solar hot water?  Well...first, I'm not sure if my desuperheater and solar hot water can work together...but let's assume they can.  A solar hot water system (which is not a do-it-yourself job for me given my roof is so steep) would probably cost about $5000 installed.  This is just a guess looking online for similar systems.  What's the ROI?  16.8 years...so yeah, that's out of the question.

Out of these 3, upgrading the computer has the best ROI, albeit the overall savings are small.

However, I think my best bet is going to be contacting my geothermal MFR to see if there's a way for my desuperheater system to heat my hot water.  All the parts are there...there just needs to be some way for the hot water tank to contact the geothermal system to turn on.  And in hot water only mode, then the geothermal system would not turn on the fan.

Info on geothermal

Since I get asked this a lot...below is a link to an explanation of how geothermal (ground source) heat pumps works:

 http://www.geoexchange.org/index.php?option=com_content&view=article&id=48:geothermal-heat-pumps&catid=375:geothermal-hvac&Itemid=32 

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