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I had the pleasure of presenting a talk titled “Daylight for Comfort and Profit” at the local United State’s Green Building Council’s (USBGC) Green N Grub presentation last week.  It was located in the Greenwood Village Town Hall Community Room, a good location, as it enabled me to discuss the lost opportunities for daylighting that are present in so many of our public buildings.  We entered the building into a high ceilinged atrium with a central skylight and east/west clerestories which should provide daylighting.  And yet, every electric light was turned on in the midst of a beautiful sunny Colorado fall day.  I asked a Greenwood Village staff member if he know how to turn off the lights or even knew where the light switches were, and he responded that he did not.  Nobody there could recall those lights ever being turned off.

The essence of the talk was that daylighting can be used to simultaneously improve life for occupants of such buildings while reducing energy cost.  Research now demonstrates that the benefits of daylighting extend to a wide variety of building types, including office, retail, health care, and education. Interestingly, the research also demonstrates that poorly implemented daylighting has a detrimental effect.  Successful daylighting depends on mastering a large number of critical details, so that glare and excessive contrast ratios are avoided, while providing useful ambient light.

Because electric lighting can consume as much as 25% of total electricity use, 40% of total energy cost, and contribute as much as 47% of greenhouse gas, it is a logical place to look for savings.   In our building projects, we assume we can cut that electric light bill in half, and sometimes even more, saving our clients substantial amounts of operating cost if the electric lights are off.  And that is where most daylighted buildings fail, just as in our host building.  Getting the lights turned off when daylighting is adequate is the greatest challenge we face as daylight designers.  And in order for that to happen, a good understanding of the emerging field of Human Factors is helpful.  But that’s a topic for another day.

By Paul Hutton

Pouring rain.  Muddy paths.  Beautiful sunsets.  Those are some of my strongest memories of the three days I spent in Washington D.C. judging the Solar Decathlon, the U.S. Department of Energy’s competition, challenging collegiate teams to design, build, and operate solar-powered houses that are cost-effective, energy-efficient, and attractive. The winner of the competition is the team that best blends affordability, consumer appeal, and design excellence with optimal energy production and maximum efficiency.  In the end, the outstanding the quality of the houses overcame all of the adverse and distracting circumstances.

There were 19 entries from the United States and four foreign countries – Canada, China, Belgium, and New Zealand.  Our work visiting each project both during the day and at night (in order to properly evaluate lighting design) was exhausting, but the enthusiasm and passion of the students made it all worthwhile.  Now that I have had a couple of weeks to absorb what I saw and experienced, some patterns begin to emerge.  I would summarize them this way.

In general, the entries demonstrated that a net zero energy house can be achieved using existing off-the-shelf technology and without extraordinary expense.  Compared to the first Solar Decathlon in 2002, there are so many more products available to achieve high levels of energy efficiency.  Just a few of them are triple pane windows, energy recovery ventilators, and affordable photovoltaic (PV) panels.

Since the first Solar Decathlon, there has been a reversal of the trend toward ever-larger average house size in the United States.  New houses are getting smaller in response to the economy and the Solar Decathlon is thus more relevant than ever before.  The size limit is 1,000 gross square feet so every entry demonstrated creative use of space or innovative ideas for multi-use space. 

There was a surprising variety of attitudes toward one important aspect of residential design – privacy, both visual and acoustic.  Contestants were allowed to choose a market segment so our jury did not penalize any project for lack of privacy or reward others for better privacy.  Perhaps it’s a reflection of the lifestyle of our college-aged contestants, that the concern was completely absent from a few projects. 

Apparently, there is a possibility that the Solar Decathlon won’t be held in Washington D.C. next time.  That would be a shame, as the location has the potential to draw large crowds.  On the other hand, perhaps it’s time for the Decathlon to move about the country, just as its namesake – the Olympics – moves about the world.  And why not Denver for the next one? 

By Paul Hutton

In our continuing effort to assist clients achieve the most high performing, energy efficient buildings, we recently studied the energy consumption in area churches.  The study compared energy consumption at twelve churches over the period from June 2009 to May 2010.  The churches range in size from 7,400 square feet to over 75,000 square feet and are between five and well over seventy-five years old.  A number of churches also house some type of full-time educational program, such as a day care, preschool, or day school.  In these cases, data was included in both the overall group as well as in a separate category.

Data from a 2003 Department of Energy Survey indicates that congregations in the United States spend between $0.25 and $1.30 per square foot annually on energy.  While consulting with Xcel Energy, we determined that a precise update of this data to define an accurate range of energy costs for local area churches is not available.  However, our interpolation of energy cost inflationary data suggests that all of the churches in our study would fall within an updated range. Based upon usage during the study time frame, the average congregation in the study spent $1.07 on energy with a range of $.39 to $1.91 per square foot per year.

Most of the churches expending less than $1.00 per square foot have worked to control their energy costs through efforts such as installation of improved lighting and lighting controls, careful monitoring of peak electrical consumption, and improved HVAC controls.  These often low cost and simple solutions can provide significant savings to a congregation.  However, there are other simple solutions we’ve utilized throughout our 20 years of sustainable design that could also be applied to church facilities, including improving the performance of the building envelope by sealing leaks, adding insulation, and replacing poor performing windows.

We are always looking for more churches to participate in the study.  If you are interested, please don’t hesitate to contact us!