Energy Audit Lab
Collaborators-
Griffin Matthews
Griffin Matthews
Abstract-
An experiment was conducted to better understand the energy efficiency of the house. The results were that the house uses substantially less electricity than the average US home. The kWh meter was measured within a 4 hour window each evening for 10 days consecutively. The weather observations and notable appliance usage were also taken each day as evidence for sudden rises or drops in daily kWh usage. The house used 148 kWh of Wake Electric electricity over the course of 10 days and used, on average, 16.444 kWh of electricity a day. The spikes in the kWh per day chart are due to appliance use and, most notably, the outdoor hot tub that caused significant rises in kWh usage, twice. The production of the electricity used by the home and produced by Wake Electric emitted 106.56 kg of CO2 and 0.444 kg of SO2 in only ten days. The electricity is produced from a roughly 50/ 50% mix of coal and natural gas. The bill average cost per day was around $2.89, according to the latest bill.
An experiment was conducted to better understand the energy efficiency of the house. The results were that the house uses substantially less electricity than the average US home. The kWh meter was measured within a 4 hour window each evening for 10 days consecutively. The weather observations and notable appliance usage were also taken each day as evidence for sudden rises or drops in daily kWh usage. The house used 148 kWh of Wake Electric electricity over the course of 10 days and used, on average, 16.444 kWh of electricity a day. The spikes in the kWh per day chart are due to appliance use and, most notably, the outdoor hot tub that caused significant rises in kWh usage, twice. The production of the electricity used by the home and produced by Wake Electric emitted 106.56 kg of CO2 and 0.444 kg of SO2 in only ten days. The electricity is produced from a roughly 50/ 50% mix of coal and natural gas. The bill average cost per day was around $2.89, according to the latest bill.
Problem-
How energy efficient (electricity wise) is the house being tested?
How energy efficient (electricity wise) is the house being tested?
Materials-
- kWh meter. These are on all US homes with electricity supplied by companies.
- Chart to record data.
Methods-
- Acquire a chart or notebook to record data.
- Locate the kWh meter. Located somewhere around the house, usually outside.
- Record the kWh reading (read on the meter) on the chart. Record the weather and Notable appliance usage.
- Repeat step 3, at the same time, everyday, for ten days.
- Look at the chart and calculate the daily kWh usage and find the average.
- Look for a trend and see if appliance usage and weather conditions correspond with the daily kWh usage.
Data-
16.444 kWh a day on average.
The Temperature was mostly in the 60's (Fahrenheit) for the entire 10 days.
The Temperature was mostly in the 60's (Fahrenheit) for the entire 10 days.
* $89.66 is the cost of the electricity, not including taxes and no energy use related fees.
SO2 and CO2 emissions
SO2 and CO2 emissions
Coal and natural gas is the main source of energy from Wake Electric.
Looking at the May/ April/ March kWh usage, it is estimated that air conditioning in the summer months more than doubles the kWh usage. For example, May's kWh usage was 452 and June's kWh usage was 939. Consequently, this doubles the price due to air conditioning.
House Information
Looking at the May/ April/ March kWh usage, it is estimated that air conditioning in the summer months more than doubles the kWh usage. For example, May's kWh usage was 452 and June's kWh usage was 939. Consequently, this doubles the price due to air conditioning.
House Information
- The house has fiberglass insulation, R49 in the roof, R18 in the walls, and R25 in the floor.
- Slight shade from trees in backyard, however, this probably won't affect the data much.
- Dark Grey, 10 year old roof. Good condition. Architectural shingles.
- Excellent circulation in the attic. The attic has multiple open air vents to the outside. There are also ridge vents along all ridges of the roof.
- Most doors are tight, however, a few doors have small gaps that have been filled to the best of the owners ability with weather stripping. Nevertheless, there are still small holes.
- The outside walls are a beige/ tan color. This reflects heat.
- Other features would include 2 air conditioning units, one for each floor. So, this enables the house to only heat one floor at a time.
Data Analysis-
Things that should be mentioned that use substantial amounts of electricity include the timer lights on the front porch, foyer, outside the garage, backyard, and living room. All of which run anywhere from 3-5 hours. Probably the biggest kWh user in the house is the 225 gallon hot tub that runs on a second 50 amp circuit breaker. The hot tub is not on all the time and is only turned on for five hours at a time, once or twice a week. The hot tub was the cause of the two 200% data spike in the graph. It should be stressed that 50% of the time, only one person occupies the house and the other half of the time there are 2 people living there. This is a probable factor as to why the kWh usage (444 kWh a month) is so low compared to the national average of 940 kWh a month (EIA). During the time the test was done, the home had glowing halloween decorations that used up some power and the last 2 days of the test, no one was in the house so the only energy use was from the timer lights alone. The temperature was in the 60's all week, so, no heating or air conditioning was turned on. Wake Electric gets none of their energy from Shearon Harris Nuclear Power Plant, so none of our energy needs are contributing to creation of heavy radioactive waste. However, the coal and natural gas does produce substantial amounts of SO2 and CO2.
Things that should be mentioned that use substantial amounts of electricity include the timer lights on the front porch, foyer, outside the garage, backyard, and living room. All of which run anywhere from 3-5 hours. Probably the biggest kWh user in the house is the 225 gallon hot tub that runs on a second 50 amp circuit breaker. The hot tub is not on all the time and is only turned on for five hours at a time, once or twice a week. The hot tub was the cause of the two 200% data spike in the graph. It should be stressed that 50% of the time, only one person occupies the house and the other half of the time there are 2 people living there. This is a probable factor as to why the kWh usage (444 kWh a month) is so low compared to the national average of 940 kWh a month (EIA). During the time the test was done, the home had glowing halloween decorations that used up some power and the last 2 days of the test, no one was in the house so the only energy use was from the timer lights alone. The temperature was in the 60's all week, so, no heating or air conditioning was turned on. Wake Electric gets none of their energy from Shearon Harris Nuclear Power Plant, so none of our energy needs are contributing to creation of heavy radioactive waste. However, the coal and natural gas does produce substantial amounts of SO2 and CO2.
Conclusion-
The energy efficiency is surprisingly low for what was expected. A way to reduce energy use would be to cut back on the timer light usage as there are 12 lights all around, inside and out, that are on every night. Another possibility is to switch to florescent lights. The majority of our light bulbs are incandescent. One issue we have found with florescent lights is the short life span of them. This entirely goes against what is advertised by the companies, but I have yet to find a light bulb that lasts 25 years like the companies say. Regardless, it would be more energy efficient at the cost of changing light bulbs a little more often. We have fairly good habits in terms of heating and air conditioning usage, so, we don't waste to much energy in maintaining an indoor climate. On the subject of the incredibly electricity thirsty hot tub, I am starting to wonder if turning the hot tub on for a half hour a day to keep the temperature up would be more efficient. This would stop us from using electricity to heat up 225 gallons of water from 50 degrees to 105 degrees every week. A topic for a later experiment. The hot tub does have some energy saving technologies in place, such as the insulating cover and a system to shut the power off after it hits the desired temperature. All of these suggestions lessens our need for energy from the electric companies and lessens our carbon footprint by taking away from the SO2 and CO2 produced by the power plants. Overall, I think the experiment went well, but, I feel my measurements should have been taken everyday, on the hour, not in a 3-4 hour window.
The energy efficiency is surprisingly low for what was expected. A way to reduce energy use would be to cut back on the timer light usage as there are 12 lights all around, inside and out, that are on every night. Another possibility is to switch to florescent lights. The majority of our light bulbs are incandescent. One issue we have found with florescent lights is the short life span of them. This entirely goes against what is advertised by the companies, but I have yet to find a light bulb that lasts 25 years like the companies say. Regardless, it would be more energy efficient at the cost of changing light bulbs a little more often. We have fairly good habits in terms of heating and air conditioning usage, so, we don't waste to much energy in maintaining an indoor climate. On the subject of the incredibly electricity thirsty hot tub, I am starting to wonder if turning the hot tub on for a half hour a day to keep the temperature up would be more efficient. This would stop us from using electricity to heat up 225 gallons of water from 50 degrees to 105 degrees every week. A topic for a later experiment. The hot tub does have some energy saving technologies in place, such as the insulating cover and a system to shut the power off after it hits the desired temperature. All of these suggestions lessens our need for energy from the electric companies and lessens our carbon footprint by taking away from the SO2 and CO2 produced by the power plants. Overall, I think the experiment went well, but, I feel my measurements should have been taken everyday, on the hour, not in a 3-4 hour window.
Citations-
United States. Energy Information Administration. N.p.: n.p., n.d. Print. (Referenced in the Data Analysis)
United States. Energy Information Administration. N.p.: n.p., n.d. Print. (Referenced in the Data Analysis)