Energy Efficient at the 48th Parallel


 Sometimes you stumble on a place, and you just have to live there.  Sometimes you have a life-long goal that requires real effort to realize.  We encountered both when we found a tiny town in the Far Pacific Northwest and decided to build an energy-efficient, “solar home” there. 

Being an engineer, I like lists.  My wife indulges me in this.  For years we maintained a list of weighted criteria to help us find a great place to live.  Each year, we’d do research on the Internet and read about several places.  For our summer vacation, we’d go to the place that looked best.  Eventually we found a spot ‘way up, near the “edge” of the Lower Forty-Eight.

How far up?  We’re talking 48° north latitude, here.  Natural beauty abounds.  Deer romp and generally do deer stuff all over the place.  Ditto crows and the occasional coyote.  Orcas ply the waters of Puget Sound.  Fog horns at night.  Giant container ships sail past on their way to the Port of Seattle.  You get the picture.

We’re both telecommuters.  We looked for a small house that had the right layout for two home offices but couldn’t find much.  We did, however, find a nice lot right in town.  Great southern exposure.  Walk to uptown or to the Sound.  City utilities in place.  We decided we’d take some time and have a house built.  We were living in northern Colorado at the time, so we made many trips out here to interview contractors and go over plans with the architect.  We knew that long-distance managing a project of this complexity and importance would be a real challenge.

Now we aren’t into ostentatious stuff at all.  We wanted modest, homey, and energy efficient.  After all, we’re thinking that we’d like to retire here someday, and it is just possible that energy prices could (ahem) continue to increase over the next couple of decades.   

We found that lots of people heat with wood here.  Natural gas isn’t even an option in this area.  Propane is expensive, with great volatility in price.  Others go with all electric homes.  The climate is not too challenging.  Winters are pretty mild (a low of 20°F is a good design parameter).  Summer highs in the high 80’s are cause for lots of complaining and discussion at the local coffee shop.


What We Did 

As far as our energy strategy goes, we decided on the following:

1.Use the south facing property to build a passive solar design.  Put in lots of south facing glass.  Overheating is not a problem in spring and fall, and we want to grab as much solar energy as we can on most days year ‘round.  Put very little glass on the north.  Shade the windows on the west side of the house with a garage and some trees.

2.Insulate, insulate, insulate.  We used R-60 BIB (Blow In Bats) in the attic.  R-30 in the walls.  0.29 U factor windows. Even the slab in the basement is insulated.

3.For HVAC, we chose a closed-loop-ground-source heat pump.  Basically, if you dig down about 6 feet, the soil temperature is always about 50°F.  If you run heat exchange pipes at that depth, you can pull heat out of the ground all winter long. It’s just about as efficient as it gets.

4.We decided that the ultra-tight building envelope merited some action to keep the indoor air quality high without opening a bunch of windows in January.  To accomplish this, we added a “Heat Recovery Ventilator” (HRV) to the HVAC system.  This is basically an air-to-air heat exchanger that uses waste heat from stale air to pre-heat fresh air drawn from outdoors.  Although an HRV uses some energy, it claims to be over 90% efficient.

5.Since my office is in the basement, we augmented the heat pump system with some radiant floor heat.

6.We have a small, efficient wood stove in the main living area of the main floor.  On days with no appreciable sun, we can warm the main living area very nicely with this stove.

7.Energy Star appliances.

8.Simple, inexpensive things count too.  We used compact fluorescents in nearly every light fixture in the house.  Since CF's are nearly six times more efficient than incandescent bulbs, this really adds up.

9.Switched plug strips all over the house to cut down on phantom loads.  Since we were building the house from scratch we even put a switched circuit in the main living space so that we could power down the entire entertainment system.  No energy leaks there.

10.Finally, we put a 4 kW PV array on the south facing roof.  Washington State has a very good renewable energy incentive program.  While it’s a big ticket item, putting in a good size array takes a big bite out of energy bills in an all-electric house.


Performance So Far

We moved into our new place on the last weekend of March, 2008.  Much of April was consumed with unpacking and setting up our household.  I started careful tracking of energy use and energy generation in May.  May was still very much a “heating month” on the north end of the Peninsula this year.  In May, the PV array produced 35% of our total energy needs.  In June, it produced 44%.  In July, 49%.  In August the array supplied 47% of our total electrical needs.  Since this is an all-electric house, these numbers are significant. 

August started out hot and sunny and we had several days in which we generated more than half of our total energy usage with the array.  Of course the weather here can get overcast and rainy, and at the end, August turned out weaker than we’d hoped.  Old timers say that good weather often stays with us well into November.  I hope they're right.


What We Have Learned

We are satisfied with the overall energy performance of our home.  We've learned quite a bit in the process of building it.  Probably our biggest learning was that remote house building turned out to be even harder than we anticipated.  The general contractor we chose was good with telephone and email and was very responsive.  He also was enthusiastic about the project from start to finish and was basically great to work with.  Had it been otherwise, the experience may have been somewhere between a nightmare and a disaster.


Do we plan to expand the energy systems?

To answer this, we need to consider energy costs in the context of other operating expenses.  In July, our total energy bill was less than $30.  That's only about 25% of our monthly telecommunications expenses and less than half of our water bill, so from a purely financial perspective, I don't think we could justify another large expenditure for energy systems at this time.  We might want to look at rain catchment first.  It is low-tech and will probably have a fast payback.  My wife is, after-all, an avid gardener.  Reducing our water usage has a stronger return on investment than other, more expensive energy system enhancements. 

I think our biggest controllable energy expense is probably hot water.  Here, we were at the mercy of local subcontractors who had limited experience with unusual systems.  If we had a do-over, I might insist on a simpler hot water system with a solar thermal assist.  If we do decide to expand our energy system, this would be the top priority.


Would we do the whole thing over again?

The tight building envelope is a no-brainer.  So is the passive solar design.  We have both noticed many cool days when our house is cozy and warm with the heat turned off while some of our neighbors are obviously feeding their wood stoves as fast as they can.  

The closed-loop-ground-source heat pump system was expensive, and in retrospect I wonder if we truly needed it.  If the HVAC subcontractor had been willing to acknowledge that the house was designed to need little heat and then install a somewhat smaller system, the net expense difference would have been very small.  As it turned out, the HVAC subcontractor insisted on his standard formulas for figuring out system size.  This is a common problem with high efficiency houses. If we had been local and able to have face-to-face meetings, we might have been able to influence the subcontractor better.  On the other hand, the system works beautifully, so I can’t say that this is a mistake either.

The PV system has performed flawlessly and exactly as predicted for this locale.  There were no surprises and the contractor was excellent.  I'd do that again in a minute.  Doubling the array size to 8kW would get us near the break-even point in energy usage.  


Conclusion

Our house is warm, light, and cheerful.  It's also quiet, efficient, and modern.  Overall, we enjoyed the process of building our home and are happy with the result.  The house itself gives us hours of fun activities as we measure, design, plan, and build.  We realize of course that not everyone has the time, energy or desire to interact with a home in this way, but we enjoy it a great deal.   

What's next?  Our next projects focus on serious gardening to produce fresh, healthy food.  Taking transportation costs out of the food supply is one more energy saver.  Fresh, tasty produce is just plain good.  We have already added a greenhouse.  This will enable us to start plants next January or February and may allow us to grow fresh tomatoes in the winter.  I can hardly wait until I finish cultivating our main garden area...

© Michael C. Glaviano 2009 - 2016