A Shocking Analysis Electricity Bill Evaluation IME 301 Brendan Cheng Hey everybody. My name is Brendan Cheng, and I chose to evaluate my parents’ electricity bills for my project. I have found some very interesting things about how our bills have changed over the years. This is the shocking analysis.

Project Overview Problem: Determine how much electricity we consume (in kilowatts) and how much it costs us on a timely basis Hypothesis: I expect to see that our electricity usage and cost is highest in the summer. Data Collection Monthly electricity bills from 2003 to Present Number of people in household Project Overview. Electricity has become an essential part in our everyday lives. Every thing we do requires electricity. For my problem, I wanted to determine how much electricity our family consumes and how much it costs us on a timely basis. My hypothesis is that I expect to see that our electricity usage and cost is highest in the summer. Data Collection. I collected our family’s monthly electricity bills from 2003 to present. I inputted my data into an excel spreadsheet, and recorded information on the cost per month, cost per season, cost per year, usage per month, usage per season, usage per year, cost per kWh per month, and number of people in the household.

Cost/month Frequency Cost ($) Here is a histogram of the costs per month. We can almost see the data forming a normal curve. For the majority of the months, my parents spent between $58 to $209 (which are represented by the 3 tallest bars). Furthermore, for 40 separate months, my parents spent between $109 and $158. In total, I have 86 monthly bills plotted. This means almost half the time, my parents are spending around 109 to 158 dollars a month. There is an extreme outlier on the far right side. This outlier occurred in the month of July, 2006, and the bill cost us $511.96. I looked up historical weather records and found that this month was very dry and hot. Weather ranged from 90 to 110 degrees. This means our house must have had the A/C on full blast all day long. This would account for the very high cost. Cost ($)

Cost/season Cost Season This is a box plot of the costs per season. Basically I separated each year of data into 4 seasons. Than I put all the fall seasons together, the winter seasons together, and so on. From analyzing these plots, we can see that the cost during summer was the highest. The average cost of the summer season was roughly $490. The next highest average was found to be in the fall and that was $420. This means that on average, our family spent $70 or more in the summer compared to any other season. Spring ended up being the lowest costing season. This is due to the account that it is neither hot or cold in this season; it is usually perfect weather. So, we have no heater or A/C on, and this reduces the cost of our bills. Also, only three people are living at home compared to five in the summer. Although the graph does not show, there is an extreme outlier in the summer box plot ($796.18). This occurred in the summer of 2006. Like I stated in the previous slide, this summer was very hot and dry. So we used a lot of electricity, which in turn, raised our electricity bill. Season

Average Cost/Kwh Cost/kWh Year Here is a bar graph showing the average cost per kWh. I separated each year into the four seasons: fall (teal), winter (blue), spring (yellow), and summer (red). Than I took the average cost per kWh within each season. This bar graph clearly shows that inflation has occurred over the years, peaking in 2006. In 2003, the cost per kWh was around $0.12, but in 2006, it shot up to around $0.17. In the previous slide, we saw that the average cost in winter and spring were much lower than in fall and summer, but in this bar graph, the cost per kWh in winter and spring is higher than fall and summer. Basically, this means that our electric company was charging us more money in the winter and spring for less electricity. Also, we can see from the graph that the cost per kWh in summer is usually the cheapest in the year. Although the electric company may charge us less in this season, they still end up making much more money because of the amount of electricity we use. Year

Kwh/season kWh This is a box plot of the kWh per season. I used the same method in the creation of the cost per season box plot to make this graph. In the summer, our family consumed on average 3563 kWh. Just looking at the graph, we can see that the kWh usage in summer is much greater than any other season. Here are a few reasons that explain for the high kWh usage: 1) My other brothers come home from college in the summer. More people at home means more electricity used. 2) It is hot in the summer. The A/C is always on in our house, and the A/C uses a lot of electricity. 3) Everything fun in our house uses electricity (video games, computer, T.V., etc.). Since school is out, we have no homework to do, so we are constantly using these devices. The seasons of fall, winter, and spring have a relatively low average kWh usage compared to summer. Since we have less people home and the A/C isn’t always on, electricity usage significantly decreases in the other seasons. Season

Cost/Year Cost Year Year Here is a display of the costs per year. In 2003, we had 5 members of our family living at home. From 2004 to 2008, we had 4 members at home and in 2009, only 3. This graph further emphasizes that inflation has occurred between 2003 and 2006. Even though we only had 4 members at home in 2006, compared to 5 in 2003, the average cost per month went from $102.04 to $176.59. After 2006, you can see that the cost per year slightly decreases and stabilizes for a couple of years. The cost per year further decreases in 2009 because there were only 3 people living at home this year. There is an extreme outlier in the year of 2006. This was the same outlier in the very first histogram, July 2006 ($511.96). Year Year

Conclusion Prediction: Cost and kWh usage will be most in the summer Actual Result: Cost and kWh usage was highest in the summer Interesting Facts What I learned Questions? Conclusion. I predicted that the cost and kWh usage would be the most in the summer. After analyzing my data, I found my hypothesis to be correct. The cost and kWh usage was highest in the summer. Now, here are some interesting facts about my project. The most expensive month occurred in July 2006, and it cost $511.96. The most expensive season was in the summer of 2006 and that was $796.18. The most expensive year was also in 2006 which was $2107.10. Apparently, everything happened in 2006. The highest kWh usage in a month was in July 2006. We used 2230 kWh. The highest kWh usage in a season was in the summer of 2006 which was 4206 kWh. Surprising the highest kWh usage in a year did not happen in 2006 but in 2005 with 12862 kWh. From this project, I have learned that electricity bills are not cheap at all. For the total cost of these past 7 years, we have spent over $11000 on electricity alone and used over 78000 kWh of electricity. After looking at all of this, I have realized that I am wasteful when it comes to using electricity, and I will find ways to reduce my usage. Simply turning the lights off when it’s not needed could save hundreds of dollars. Thank you for listening to my presentation. Any questions?