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Audits at Warren Wilson:

 

The Water and Energy Efficiency Crew’s job here on campus is to make sure buildings are using energy efficiently. We’d like to update the Warren Wilson community updated on what we’re doing on campus. The projects we are working on now are in Shepard, the Garden Cabin, various faculty/staff houses, and Devries Gym.

 In Shepard the crew has inspected all doors and windows, checking for any openings from which heat could escape. We have found that most windows are warped. This prohibits the windows from shutting completely. Also, all the doors in the house but one were missing weatherstripping, besides one. We have started to resolve these problems by first installing weatherstripping on the doors in need.

In the Garden Cabin, we have gone through and taken note of how the cabin is heated, how often electrical appliances are used, and what type of lighting is present. The cabin is heated by a small gas space heater down stairs and an electric space heater upstairs. Because the structure has wood walls there is no other kind of insulation. We found that the doors were letting out a lot of heat. In order to try to make the cabin as efficient as possible our crew has worked on straightening the doors and applying weatherstripping. The lights aren’t all high-efficiency so we are in process of completing as cost benefit analysis to find out whether or not it would be worth the money to replace them with compact fluorescent bulbs. As far as appliances go there were two refrigerators in use. Because all the food stored in the two refrigerators can be stored in one, we decided to put one on a power bar so it can be turned off and easily turned on for use at parties or other activities.   Recently we have made further improvements  by  installing weatherstripping  on the front door.   After installation we noticed  that two boltz  sticking out from the door were cutting into the weather stripping.  We sawed off the boltz  making them  flush to the door to prevent interference with the weatherstripping.   On the side door there are gaps around the outside.  We are cutting wood strips about 1.5 or 4 inches wide to apply to  the door frame to close the gaps.  When that is completed we are installing weatherstripping  to the wood strips  to make the door air tight.

We have also performed tests with both our blower door and infrared camera. To perform a blower door test, we close all the windows and doors in a building. In one outside door we install the blower door. As the test runs, the fan in the door pushes air outside the house, lowering the air pressure inside. The difference in air pressure inside the house and outside the house causes air to be sucked inside through all the cracks in the foundation, walls, floor, and ceiling. The blower door and its software are sophisticated enough to tell us exactly how many square inches of opening to the outside the house has. It can also “cruise” at a high pressure difference so we can survey the building and feel around doors, windows, electrical outlets, etc, to find exactly where the most amount of air leaks in. In conjunction with the blower door test, we also take images with our infrared camera. Because we are sucking cold air into the house, when we take an image the leakier areas show up very well. In this way, the infrared camera helps us locate air leaks, but it also helps us find poorly insulated areas. A building may be airtight and still lose a lot of heat if the building is constructed with materials with low thermal resistance.

One of my favorite projects is at 106 North Lane. This is staff housing and our crew was sent to audit it before the new owners moved in. Our crew has been working hard on making this house as efficient as possible for the new owners, who are absolutely wonderful people. The new owners are Tom and Melanie and their son Josiah. Tom is the supervisor of the heavy duty crew. I have greatly appreciated the time our crew has had fixing the house while talking to Melanie about how to create a stronger, more conscious community. Of course playing with Josiah (who is one of the brightest little boys I have ever met) has been great. Our crew has performed the blower door and infrared camera tests to measure air tightness. In response to what the tests showed we sealed and insulated all of the overhead lighting fixture and all electrical outlets. We also taped up the attic door. We then did a second blower door test to see if we made any improvement. We did make a significant improvement, but we still need to install weather stripping on two doors before we do another test to find our total energy savings. By doing simple and easy improvements to the air tightness of a building, it is easy to reduce energy bills and carbon footprint.

We are beginning to expand to more on-campus faculty/staff housing so we will update this section as we proceed.

Another building we have on our to-do list, is Devries Gym. Devries is the biggest energy user on campus. We haven’t delved into the job, but have walked through the building several times to try to understand some of these problems: the pool is not well insulated because the walls are built with concrete block and steel, neither of which have high R-values and therefore with transmit heat easily; there are few light switches easily accessible anywhere in the building; the doors and windows are very leaky and most lack weather stripping. As we continue to get more organized and ambitious we will spend more time at Devries in an attempt to reduce its energy use.

  

The Great Chapel Mystery That’s Got Everyone Wondering

By Kate Collins

The WEE crew looked at the energy consumption of the chapel from year 2004-2008 and found that the power and energy use in this building has risen significantly over each one of those years. In 2005, the total kilowatt-hours for the chapel was 22098, followed by 24877 kWh in 2006, and then by much higher 34751 kWh in 2007. In 2008 so far, the chapel has used 23693 kWh just from January to September. From 2005 to 2007, our school has paid an extra $1265.30 per year just for the extra energy consumption in this building. What’s up with that? Are there just more people coming to Warren Wilson? Could there have been more extreme weather each year?

        The heating degree days show that the winters in Asheville have not changed significantly over the past few years, so let’s rule out the weather as a possible reason for the great chapel mystery. A degree day is a measurement of heating or cooling. Weekly or monthly degree-day figures and are used to monitor the heating and cooling costs of air-conditioned/heated buildings, while annual degree-day figures are used to predict future costs. Heating degree-days (HDD) and cooling degree-days (CDD) are designed to show the demand for heating/air conditioning energy. Daily temperature observations and heating/cooling requirements for a given structure are directly connected to the number of overall degree days at that location. The number of heating degrees in a day is defined as the difference between a reference value of 65°F (known as the base temperature) and the average outside temperature for a 24-hour period. If the average temperature for a given day is 50°, then it is a fifteen degree-day because this number is fifteen degrees away from 65°. Temperature throughout a day is not always constant, so we take the average temperature by finding the mathematical mean of the high and low temperatures for the day. Degree-days can technically be calculated using any base temperature depending on the temperature in a given building. Our work crew is going to use degree-days to monitor the use of power and energy in the heating/cooling systems of our school’s structures so that we can use less and waste less. The average yearly heating degree-days in Asheville, NC is 4308, and the average cooling degree-days in the area is 787.                                                                 
        We can therefore not attribute the increase in energy to the weather. The next subject for our examination was the lights. The lights in the chapel are on every day and every night even though the light switches are in a place that anyone can access. There are a total of 54 incandescent light bulbs and we estimate they are about 100 watts each. These lights are less efficient than other light bulbs that have lit the chapel before 2005. Most of the lights are on dimmers, which can make the watts and kilowatt-hours vary from light to light. However if all the lights are on at once continuously, that’s 5400 watts of power and 1000 kilowatt-hours per month. If the lights are on for 200 hours every month and/or the new lights are less energy efficient than the old lights, that could more than account for the extra use of energy. The reason the energy in the chapel is so expensive is because the lights are on all the time, even when nobody is inside.

Since the turning off lights thing isn’t working out, we came up with what seems like a simple solution, if it exists. We wanted to put in passive infrared motion sensors to ensure that the lights go off whenever nobody is using the building. Then when someone is in the building, the lights could automatically go on. The PIR (passive infrared) sensor is a surveillance tool which when detects heat, the lights turn on. You’ve seen such sensors in peoples’ yards; you know those lights that go on for detecting when you step into someone’s driveway used for exposing burglars. This tool can usually detect objects from dozens of feet away. The PIR is inexpensive so maybe we could put some in a few places where people can easily walk by them or find them in the dark. The lights stay on as long as motion can be detected or for about thirty minutes. Since the cost would be too high to break open the ceiling and walls of the church to install one of these tools and all its cords and then close the walls and ceiling back up, we are looking at wireless PIR sensors to somehow connect to the lighting system. Most PIR sensors are motion sensors connected to one light bulb, but we need one that we can wirelessly connect to all the lights in the church. Since the chapel has been using $1265.30 extra per year, we would need to be able to install this device for less than that cost. One of the PIR sensors could be connected to all of the extravagant lights in the chapel.

Now, as we’ve just been informed by Donna Joslin, the lights have been left on intentionally over the past few years because the chapel has been vandalized twice with fire extinguishers. The lights are on to make the building look like it’s always being used to drive away potential vandals. We would have found this out during our attempt to get permission to install the PIR sensors. The cost of repairing more vandalism would apparently be higher than all the extra cost of keeping the lights on. Moral of the story: don’t vandalize campus buildings because the extra work it takes to prevent vandalism is financially and environmentally costly.

 

We came up with yet another idea on how to save energy in the chapel while still having it appear to be in use during the night. We want to install a PIR sensor outside, so when someone is near the chapel, the lights go on inside. It will be designed so that the naughty person doesn’t know that they’ve made the lights go on, but they’ll think that someone inside the chapel turned the lights on and they’ll ideally run away. We found a device that we think we could use for this. We want the outdoor sensor to plug in to an outlet so that we don’t have to worry about batteries running out, and we found a device that does this. The sensor wirelessly connects to the lights inside the chapel to make them go on. Hopefully the security people will approve of this. I think it’s so worth a try that if it doesn’t work and someone sprays fire extinguishers all over the chapel again, I’ll clean it up myself.

 

 

 

 

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