Case Study: Annual Energy Usage In An Energy Efficient Home

[editor’s note: I changed the title to ‘energy efficient home’ from ‘passive solar’ – this post doesn’t talk about passive solar that much, I can delve into that at another post]

Wow that’s a pretty boring title for a blog post.  I figured “Murdering Fewer Mountains and Trees So I Could Play My XBox” would be a bit to melodramatic for a Saturday night.  My new year’s resolution, which I decided upon last night was I wasn’t going to spend the day on the computer.  Well I made it ’til dinner time before I just had to hop on and fire up an Excel spreadsheet, and for your benefit, a blog post.

I spent the last hour or two pulling all of our utility bills for the last year or so, and entering them into my spreadsheet.  Also I cracked open a bottle of 2010 Joel Gott California Cabernet…it’s pretty good.  Whoever brought it over, thank you.  You’re welcome back here any time. [editor’s note: my sister said she got me the wine so I wouldn’t have to drink Yellowtail.  Thanks sis.]

2010 Joel Gott 815 California Cabernet Sauvignon makes everything better.

So I looked at the energy costs from 2009 at our old house.  This was the last year I have complete records for on a previous spreadsheet.  The records I pulled for this new house span from March last year when we were still finishing the house through this month’s bills.

The old house was a cookie cutter colonial, about 2,700 sq. feet.  In 2009 there were just 2 of us and a baby.  Heating was natural gas, electric everything else including cooling.  The furnace had a humidifier too. We had city water and sewer at the old place.  Why this is important is for two reasons: city water and sewer means water magically shows up and leaves the house and we pay a bill to the utility to make that happen.  This also means we’re not really expending any electricity to get that water and send it back, as far as I know.  The old house also had about half the number of light bulbs compared to our over the top new house and it’s hundred or so light sources.  Cooking was natural gas predominantly.  Washer and dryer were electric just like in new house (we have the same appliances in the new place).  Most of the light bulbs were incandescent but many were CFL’s and a few halogen bulbs; no LED’s. Finally we had a gas fireplace but we never really used that.

The new house is about 3,000 sq. ft. and there are 4 of us in here living.  Heating and cooling comes by way of our hybrid system employing geothermal and natural gas. Our fancy system also had an air exchanger and full house air filtration system.  Water and sewer is handled by our cistern and septic systems.  Both of these run off of electricity to pump water in, filter it and send it back out after our bodies filter it a little more.  The new place also has a sump pump which runs all the time basically to keep us from going under water during wet periods.  Cooking is handled by duel fuel range, and electric appliances.  As I said the new place has a ton of light sources, i.e. bulbs, so that alone is a huge load.  Only 4 of the bulbs are LED’s (not including the range hood’s 4 LED bulbs). The rest are all incandescent light bulbs.  The fireplace is our handy-dandy pellet burning unit, and we’ve barely made a dent in our free ton of pellets we got from Northfield Fireplace. It’ll be 2014 before I have to buy pellets.  We run the fireplace every few nights when hanging out in the family room.

Usage and lifestyle are about the same in both homes, for example in terms of watching tv and play video games.  The new place does not have any electric garage door openers though, not that it matters a whole lot.  I’ve just been too cheap / broke to put them in yet.

R Family Company, LLC estimated we’d use $2,413 annually on gas and electric when they did our Energy Start rating last year.  The engineer and architect estimated the usage to be around $1,500 – $2,000 a year just for HVAC…I think.  I’d have to delve into the paper work a bit more to confirm that.  In reality we’re pretty darn close to those numbers, after considering a few things.  I added up utility costs across the four major utilities most of us pay: electric (E), natural gas (G), water and sewer (S).  Other utilities are lifestyle like phone, cable and internet so they’re not important in my calculations.  So adding up EGWS we’re at about $3,080 for the year 3/12 to 2/13.  Our 2009 total in the old house was $3,129.  So actually a little LESS in the new place.  Now there are some expenses not added into the new house such as septic service like getting it pumped out or fixed if it broke.  Same for the water system and sump pump in terms of repairs.  I did include bleach and filters for the water purification system.  HVAC filters would be an added cost in the new home too (the old place had a washable filter).  There is one bill for electric in March of last year that was $800 when we had the resistance heater in place I believe.  That throws our new house total off a bit.  If you take most of that out of the equation then we’re spot on with the $2,400 estimate Bob gave us from Energy Star.

Here’s what we paid in 2009 and what we paid in our first year in the new house (most of the year at least)

Our Natural Gas (G) usage plummeted off the face of the earth.  Dropping a whopping 90%, I don’t even think the gas furnace kicks in all.  You can see it rises in the winter, so some heat usage and probably more cooking usage as well.  Most of what we pay for gas is fees, taxes and the privilege of having access to gas.  The geothermal heating is just fine for us.  It’s not too cold or clammy like some people claimed it to be.  The fireplace is offsetting some of this too, so figure if we had to buy pellets (a $100-$250 a year maybe?) our heating cost would go up.

Electrical (E) usage is way over the top at nearly 3x the usage of the old house.  But consider: that wild March bill last year, the septic, sump and cistern all running off electric, electric oven and the biggest culprit all the light bulbs…all add up to higher (E) usage and costs.

Water and Sewer (S) costs are a fraction of what they were but once I have to maintain the systems it’ll be a wash I bet….think about replacing the septic tank, field and cistern and there isn’t enough wine in the world to make that not be a major bummer, man.

First Energy now has this cool energy usage graph that customers can utilize to see where they are spending money on electricity

Here’s another First Energy graph that highlights electric usage

I logged onto First Energy’s site and they have a new energy summary that will show you how much energy you’re using and where at.  It looks pretty good though it works off of a lot of assumptions, I’m not sure you should get too hung up on the exact numbers.  I filled in all kinds of info about my appliances and house.  I like all the color coded graphs and bars.  It even compares my house to the average house.  For electricity we barely beat out an average house ($27 per month) but for overall energy we win by a large margin ($700 annually). It’s actually embarrassing see our costs pegged all the way to the left on the little cost graph……not.  Granted these numbers are just one month’s were of data I think.  I’d have to delve into it deeper to see what a year would really save us.  Also I need to go back and look at our Energy Star docs and engineering docs to see what they estimated and where we landed.  For instance I think the engineer said about $1,000 annual saving on HVAC alone.

By the way, we keep the house at about 70 degrees throughout the year.  The fireplace thermostat gets set at 75 degrees in the evenings just in the family room area.  Personally I need to be in a certain thermal band to be comfortable so I’m not one to dial the temp up or down to far, even to save cost and planet.

I wish someone invented a smart meter, that my utility companies would support and use, that would do all this monitoring for me and just output a report on my computer or phone. Maybe I should design one.

We can save costs in the coming year a couple of ways.  Convert more bulbs to LED’s, especially the bulbs we use the most.  I plan on insulating the hot water tank. I did that in the old house.  We can insulate the basement walls even more, insulating the top 4′ that are at or above grade.  There are some air holes at the corners of some of the exterior doors that I need to close up as well.

One note, when we go to install a solar power system, having this historical electrical usage will be helpful in sizing the system. Right now it’d be difficult to go zero energy (use as much or less than we produce) because we’re at about 17,250 KWH per year.  Let’s say we had 15,000 KWH per year…that translates to a 15 KW solar system.  That would take up about 1,500 square feet of space….our garage roof is probably about 600 square feet (the part that faces southwest).  So we’d have to cover the house bits up too with solar panels.  Cost would be somewhere between $40,000 and $80,000 to install.  Not too bad considering there’s a Jeep I’d love to have that costs $40,000.  Savings over 20 years could be as high as $20,000 to $40,000 (including tax breaks and factoring in the cost of the system i.e. above and beyond).  The system would save between 400 and 800 thousand lbs of CO2 as well.  These are just wild ass guess numbers I gleaned from Dove Solar & Wind’s website while drinking my wine.  Our system would ultimately be smaller; we’d reduce our usage quite a bit and employ other goodies like solar water heating and LED’s everywhere.

Also today we went to the zoo.  They had a cool exhibit talking about collecting rain water and rain gardens.  Around this building there were two rain gardens with a “bio swale” connecting the two.  This inspired me.  We’ve got this surface water problem in the front yard that I’m going to tackle this Spring.  It’s late so I’ll talk more about it in a future episode.  For now you can look at a  couple pictures of the front yard and our temporary pond so to speak.  Night kids.

This is the little pond we get between the lawn and front bed, every time it rains or the snow melts.

Spring project will be to address the surface water issue by reworking the topography by hand to get the water to drain.