Many of you know by now I have a part time gig conducting energy assessments and energy audits for a few local power companies. Basically I help their customers who have a high bill complaint or are looking for solutions to heating and cooling problems in their homes. This week I’m going to show you a report I created for a customer. I have, of course, removed all personal information about the homeowners and the power company that serves them.
Appliances:
There are several extra refrigeration units in operation. Consolidating as many as possible and turning off all unneeded units will reduce electrical consumption.
I suggest periodically cleaning your refrigerator condensing coils. Cleaning the coils will improve the efficiency of the refrigerator and reduce run time saving electricity. I also recommend checking the temperature of your refrigerator and freezer. Refrigerators should be 37 degrees and freezers 0.
A newer option in lighting is LED or light emitting diode lighting. LED bulbs use less electricity and can last 10 time longer than standard CFL style light bulbs. Most people are used to the light output of an incandescent 60-watt light bulb. These older style bulbs were available in soft white, cool white and daylight colors. Most new bulbs have new labeling that can be confusing. LED bulbs are listed in lumens, which is the output of light. That 60-watt incandescent bulb has about the same lumens as a 9-watt LED bulb, which is around 800 lumens. A 100-watt equivalent incandescent bulb is equal to 1600 lumens. LED bulbs are also listed in Kalvin, which is the color of the light produced by the bulb. 2000-3000 Kalvin would be a warm color, 3000-4500 Kalvin would be a cooler color, and 3500-6000 Kalvin would be daylight. Try experimenting with different bulbs until you find one you like and be sure to purchase only Energy Star rated bulbs. Your power supplier has rebates available for the purchase of LED’s.
I recommend turning off all televisions and computers along with any additional equipment associated with them such as monitors and DVD players when not in use. The use of smart strips will assure that all devices associated with the computer or TV, such as monitors, and printers or DVD and stereo equipment are turned off with the main device. Many electrical devices draw some electricity even when turned off. These are called “phantom Loads” and can add to your electric bill.
If you are interested in checking any of your plug-in appliances for their energy use, I recommend purchasing a recording energy meter, such as a Kill A Watt meter. Menards has a model for sale for around $25, one can also be checked out at the public library.
Converting electrical usage to cost is done by multiplying kilowatts by the cost of power, roughly $.12. 1 kilowatt is equal to 1000 watts. Using a 100-watt light bulb as an example, 100 watts is 10% of 1 kilowatt. .1-kilowatt x $.12 = $.012. The cost to operate the light bulb is 1.2 pennies per hour, $.29 per day, or $8.70 per month if allowed to run continuously. Some electrical devices do not list wattage on a nameplate. They will list voltage, which is typically either 120 or 240, and amperage. Wattage can be figured by multiplying the voltage times the amperage. A TV that draws 2.5 amperes at 120 volts will use 300 watts. 2.5 amps x 120 volts = 300 watts. 300 watts = .3 kilowatts x $.05 = $.015 per hour. Current your power company’s electricity rates are $.1136 per KW for March-May, and September-November. $.1236 per KW for December-February, and $.1336 per KW for June-August.
You have a dishwasher present in your kitchen. Not using the drying cycle of the dishwasher and allowing the dishes to air dry will save around 50% of the energy consumption of the dishwasher.
I load checked the home entertainment equipment rack for its standby power consumption. It was drawing around 180 watts in standby, costing approximately $15 per month. I recommend turning off the power to this system’s non-critical equipment. Some equipment such as the wireless router may need to remain on. Smart home technology may help with turning off this equipment.
I tried to test the wall cooler for the wine room, but we were unable to get the refrigeration unit started. I found the unit’s info on line. It is called WineMate 1500CD. The power consumption for the unit is 480 watts. Assuming a 50% run time, the unit will cost around $20 per month.
If you upgrade any appliances or heating/cooling equipment, your power company has rebates available for the purchase of certain models. They also have several programs available to help reduce your heating costs such as duel fuel. Many of these upgrades may also be eligible for tax credits.
Mechanical systems:
You have two HRV air exchangers, one in each mechanical area. At least one of these units was in operation during the assessment. These systems are designed to bring fresh air into a home while exhaust stale air out. An air exchanger also reduces humidity during the winter months. During the summer months, when outdoor humidity levels are higher, they will bring this humidity into the home. Dehumidifiers and air conditioners often work harder to remove this humidity. If you open windows occasionally during the summertime, I recommend turning off your air exchanger from May through October.
You indicated no one instructed you on how to maintain the air exchangers. Yearly maintenance is critical for their proper operation. The following photos show the exchangers and the outdoor intake vents. Plugged intake vents can cause negative pressures within the home, causing comfort issues.
Filters inside the air exchanger and outside air intake vents need yearly cleaning. There are two intake vents, one outside the master bedroom and the second under the deck near the sauna.
There is a floor warming system in the master bathroom. The heat is supplied by radiant tubing from the ground source heat pump. There are a couple ways to set this system up. You could leave the thermostat set at whatever temperature you would like to maintain. The thermostat most likely only senses the air temperature. Ideally it would also sense the floor temperature. Depending on the heat loss in this area and the temperature setting, the floor heat would probably run more often than the forced air heat. The second way to set up this system is to replace the existing t-stat with a programmable unit and enter a program that works with your schedule. Having the heat turn on a couple hours before your normal shower or bathing time.
You indicated that you have installed a roof and gutter ice melting system, which has yet to be turned on. These heating cable systems can use large amounts of electricity if allowed to operate continuously. I recommend either plugging in only when necessary or using a timer or smart switch to control their operation.
Energy costs for a home are dictated by three factors. The cost of energy, the efficiency of the energy using equipment, and the time the equipment is in use (the efficiency of a home will affect the run time of heating and cooling equipment). A homeowner typically cannot control the cost of the energy and can only control the equipment’s efficiency when deciding which equipment to purchase. The run time of the equipment can be controlled on some equipment and devices. The use of smart home technology is becoming more common. Smart switches, receptacles, and light bulbs can all be programmed and controlled by a phone or tablet. Thermostats on furnaces and some water heaters can also be programmed and controlled by the same technology. This may be a good option for your vacation property.
Building envelope:
You are planning on replacing your roofing in the near future. This presents an opportunity to increase comfort and lower heating costs. The down side is the cost to improve the R-value of the roofing assembly is very expensive with energy cost savings payback in the decades. The roof on almost every log home I have conducted an energy audit has been the weak point of the building with regards to heat loss. Low insulation levels and poor air sealing strategies are the reason. Adding rigid insulation to the top side of the roof, along with air sealing below the insulation is the best way to accomplish this type of energy and comfort improvement. There is a recommended ratio of interior insulation to exterior insulation. In our climate, that ratio is 60% exterior and 40% interior. If your existing roof insulation is R-30, the exterior insulation needs to be at least R-40. This ends up being 8 inches of expanded polystyrene insulation (the blue, yellow or green rigid insulation). If the existing R-value is higher, the exterior rigid foam will also have to be higher. New roof sheeting is then installed over the foam and the new roof over that. There are a few additional requirements and suggestions to install this system. If you are interested in this assembly, call me. I will discuss the process with you and a roofing contractor.
That’s the report this customer received. Every home is unique and every homeowner live in their homes differently, which will effect the cost to operate the home. In this assessment, there was no blower door test conducted and no cost to the customer, the power company payed for the assessment and the customer received several energy saving devices such as LED light bulbs and water saving aerators and shower heads. This was a top ten nicest home I have been to in the 10 years and over 1,000 assessments I have conducted. A beautiful home and very nice customers!