Welcome back to our sustainable future. My name is Michael Reedy. And I want to thank you for joining me on this journey to create a more sustainable future for all of us. This module, the final one of our course is all about discovering how we, as individuals fit into the complex equation of climate change, greenhouse gases, and global warming. In other words, we're going to determine our own personal carbon footprint. And while our carbon footprint is due to many aspects of our daily life, we're going to focus on the carbon footprint associated with our residential energy, use, the electricity and natural gas we use to power and heat our homes. We'll start by determining how much energy we use and where to find the information that we need. Next, we'll learn how our electricity is produced for the region we live in. Meaning how much of our electricity comes from fossil fuels and how much comes from zero carbon, renewable sources such as wind, solar, and hydropower. We'll, then add the contribution associated with our natural gas use to heat our homes, heat our water, or cook our food. Finally, we'll add up all of our carbon dioxide emissions to arrive at our personal carbon footprint associated with our residential energy consumption. We'll also take a look at our footprint based on the more inclusive carbon dioxide equivalent, which takes into account carbon dioxide, but also several other important greenhouse gases. Once we know our carbon footprint will answer the question of well, is this a good carbon footprint? Or do I have some work to do? Another way of asking, that might be, what is our individual contribution to global warming relative to others around the United States and others around the world? This is the first step in understanding our individual impact on the environment based on how we live. We initially focus on our home energy use because that turns out to be a significant percentage of our overall carbon footprint. In the next course, in the our sustainable future sequence, we'll take a look at other contributions, such as how we get around town, what we eat, what we wear and all the stuff that we buy. But for now, let's start at the very beginning and figure out how much electricity and natural gas we use and where do we find that information? It's actually right there on our monthly utility bill. So we begin our carbon footprint journey by taking a close look at our utility bill and how to interpret what's in it. Are you ready? Let's get started. The goal of this module is to determine your carbon footprint coming from your residential energy use, meaning how much electricity and natural gas you use to power and heat your home. Yet let's first define what we mean by our carbon footprint. The Miriam Webster dictionary gives us a pretty good definition here, a carbon footprint is the amount of greenhouse gases and specifically carbon dioxide emitted by something such as a person's activities or products manufacturer and transport all during a given period. What is also important to note is your carbon footprint is determined whether you actually emit greenhouse gases directly or not. For instance, when you charge your cell phone, that by itself doesn't generate any carbon dioxide, but the power plant where the electricity comes from to charge your phone probably does emit carbon dioxide. So that's an example of indirect generation of greenhouse gases. You can also emit greenhouse gases directly. For example, if you have a natural gas, hot water heater or furnace to heat your home, then burning natural gas creates carbon dioxide emissions and those go right up the stack into the atmosphere. As you can imagine, the more energy we consume, the larger our carbon footprint and how much energy we consume is largely determined by our lifestyle choices as we'll see. So in the end, will determine our individual carbon footprints based on our current lifestyle. And what's great about this is that we'll be able to see the impact of changes to our lifestyle and how we can shrink our carbon footprint, which is our overall objective to help reduce global warming. If you think about it, anything that you do has the potential to generate greenhouse gases somewhere along the way. In this module, we're going to talk about your carbon footprint associated with residential electricity and heating. Meaning the greenhouse gases produced from the fossil fuels used to generate the electricity that powers your home. We'll also include emissions from burning natural gas or in some cases propane to heat your home, heat your water or cook your food. But your total carbon footprint involves emissions from other lifestyle choices as well. One source is the way you get around town, your mode of transportation. In this case, greenhouse gas emissions are from the gasoline or diesel, you need to drive your car. And if you're one of those early adopting EV owners and your electricity comes from a power plant and you two are generating greenhouse gas emissions to charge your EV. What we eat also has an impact on your carbon footprint. For instance, how much meat we eat versus fruits, vegetables and grains makes a big impact on our carbon emissions, not directly maybe, but in the energy and materials used to produce the food that we eat. And then it matters where it comes from and how it was grown. Was our food grown conventionally with synthetic fertilizers and pesticides? Or was it grown organically? Was it grown on the farm around the corner? Or did it travel halfway around the world to get to your grocery store? This two matters. Finally, all the stuff we have on our lives contributes to our carbon footprint. For instance, the clothes that we wear, whether they are made from natural fibers such as cotton and even that whether it was grown conventionally organically. Or whether our T shirts are made from synthetic fibers such as polyester. All this matters too. And of course, we all like to buy stuff. And as we know from earlier in this course a lot of that stuff is made from plastic. So now it matters whether our stuff comes from virgin plastic or recycled plastic. This is also true of the metals we use, like steel and aluminum and whether they are version materials or recycled. And of course, there are natural materials that can compost compared to synthetic materials that can't. How all our stuff is made is important too, as is where it is made. So to determine our total carbon footprint, we need to understand how our lifestyle incorporates all of these elements. There are likely even more than the ones I show here. But I think these capture most of our greenhouse gas emissions. For now though, let's focus our attention on your carbon footprint based on your energy use specifically the electricity and natural gas used to power and heat your home. The second course in our sustainable future looks at the impacts of our mode of transportation, food and all the stuff we buy. More importantly, we'll talk about how to minimize your Carbon Footprint by looking at more critically at what you buy, but more on that later. Let's get to our Carbon Footprint analysis. The first thing you might ask is okay, I want to know my Carbon Footprint, but how do I start? We're going to approach that question this way, first to determine your Carbon Footprint, you need to know two things. One is, how much energy you use and two, where your energy comes from, meaning how much of it comes from fossil fuels. We're going to tackle that 2nd issue in a few lessons for this lesson, we want to focus on that first question and to know how much energy you use. You first need to understand your utility bill. So for the remainder of this lesson it would be very helpful if you had your utility bill handy. Now some of you may not be responsible for paying the bill, in which case see if you can get a copy from the person who does pay the bill to learn more about what's in it. Also, many of you might have your utility set up with an auto pay system with your bank, meaning you pay your bill automatically and they never actually see the bill. If this is you, take a few minutes to download a copy of your bill now, so you can follow along As an example, let's look at a typical utility bill here is a representative monthly bill from XcelEnergy. A utility company that is headquartered in Minneapolis Minnesota but provides electricity and natural gas to many parts of the United States, including Colorado where I live. Now you're bill will probably look a bit different yet it likely has all the same information in it. So let's explore what's in this and see how it helps us to determine our carbon footprint. At the top of the bill, has all the basic information such as your name and address account information, the bills due date and how much you need to pay your utility company XcelEnergy in this example. If you go down a little bit, you see a summary of how much electricity and natural gas you consumed during the period usually the previous month and how much that costs. This is the most important information will need to determine your carbon footprint. So take note of these numbers. You can see from the bill that XcelEnergy provides both electricity and natural gas. If you don't have natural gas coming into your home then your bill will just be for electricity. You may also have one utility company that provides electricity and another one that provides natural gas. That's okay too, you just need both bills to get the information that we need. All of that is some information about your account balance and what you owe for the month. If you're a traditionalist and pay your bill by check, then the part at the bottom of the bill is the part you include in the envelope with your check. It simply states what you owe and when you need to submit payment. Now back up here towards the top is some very interesting information. The top table compares the average amount of electricity used per day during this period and what you used on average last year during the same period. That way you can compare how you're doing one year to the next. It also shows the average daily temperature during the period and that from last year as well as the cost of your electricity use this year and last year. Then there is this nice bar graph that outlines your natural gas use for each month. In this case it looks like gas use peaks in the winter months, which of course makes sense as this house likely has a natural gas furnace for heating. Below the bar graph is the average daily use of natural gas, both this year and last year again. So you can compare how much you use from one year to the next. But what we really want to explore is right here though. So let's explore this summary information in more detail which is on page two of the bill. Page two of the bill shows the electricity service details and highlights the electricity you used and how much it all costs. You probably know that utility companies figure out how much energy you use, by how much flows through a meter at your house or apartment. And every month someone from the company comes by to read your meter. Now today lot of this is done digitally and all the employee has to do is drive by and the meter sends a signal to the vehicle with all the information on it. That makes the whole process a lot more efficient for the company. The difference between what the meter read this time and what it read last time is how much you use during the month, which in this case is 1076 kWh. That's what that kWh abbreviation stands for, if you remember from previous lessons. We're going to find out that using 1076 kWh in one month is a lot of electricity. And right away we can surmise that this is a house that probably has air conditioning as it is August and likely is larger than the average house. It may also have a lot of people living there. But as this is just an example of a bill, let's keep going. This part of the bill explains how Excel Energy calculates the cost of your electricity. There's a lot here and it is rather wonky. But let's dive into this a bit deeper to see how Excel calculates what we owe them. Fortunately for all of us, we're not going to go into too many of these details yet a few of the line items are worth noting. For instance, service and facility is a flat monthly fee that covers all the administrative costs of delivering energy, including the salary of that person driving the vehicle around reading your meter. Some are tier one tells us immediately that Excel uses a tiered rate structure with the term rate meaning what it costs per kilowatt hour. Tier one indicates you get charged one rate for the 1st 500 kilowatt hours you use in this case, a little more than five cents per kilowatt hour. Summer Tier two is the rate you get charged for everything over five 100 kilowatt hours. In this case, nearly 10 cents per kilowatt hour, so almost double. And that's a real incentive to minimize our electricity use. The other big dollar figure here is the electric commodity adjustment, which is what Excel charges for all the electricity it buys from other companies. This indicates Excel doesn't own all the power plants, wind farms and solar farms in delivering its electricity. And that it contracts with third party companies to provide at least some of the electricity that ends up at your house The total at the bottom should match up with the cost of the electricity on the first page. Telling us that the electricity costs $145.95 for those 1076 kilowatt hours. There are many other line items on here that we won't go into. But essentially they represent all the additional fees Xcel energy is allowed to charge. By law they have to show all of this so we can see where our charges are coming from. And if you really want to know what all of them mean a glossary of terms is listed on page four or in this case the last page of the bill. The last page of the bill shows us the fine print explaining all of the terms used to determine your utility bill. There is usually a glossary on your utility companies website with all the details for each line item as well. Now let's go to page three of the bill, which shows us all the details of your natural gas service. Like the previous page, it highlights the amount of natural gas that you used and how much it all costs. And like electricity every month, the company reads your natural gas meter and records it here on your bill. The difference between what your meter read this month and what it read last month is how much natural gas you used. In this case 24ccf, which stands for 2400 cubic feet of natural gas. Ccf by the way means hundreds of cubic feet. The first c is the roman numeral for 100 and the cf is just an abbreviation for cubic feet. Interestingly, Xcel measures the amount of natural gas you used by volume, but it charges you in terms of heat content in the natural gas. What they do is convert the volume of natural gas you used into heat measured in units called therms. If you remember from previous lessons, 1 therm=100,000 BTUs or British thermal units. A pretty typical measure of heat at least here in the United States. In this case, the conversion factor technically referred to as the therm multiplier is about 0.857. Xcel multiplies the volume of gas you used by 0.857 to get the number of therms used to heat your home, water or cook your food. What is interesting is that the therm multiplier is different depending on where you live. It accounts for things like the altitude and the average temperature for your region. That all impacts the volume of gas flowing into your meter. Another factor is related to the methane content in the natural gas itself. If you recall, natural gas is mostly methane, in many cases more than 96%,, but it varies across the country. So the 0.857 is a number for Colorado and is affected by the methane content in the natural gas that feeds this particular house in Colorado. This section here shows how Xcel determines the cost associated with your natural gas use. It isn't as complicated as your electricity use, but still all those terms are explained in the glossary on page four and on Xcel's website. In wrapping all this up, what the bill is telling us is that this particular household used 1,076 kilowatt hours of electricity and 21 therms of natural gas energy during the month of August. And while we're at it, let's determine a few numbers that are pretty useful to know. What we pay per kilowatt hour of electricity and what we pay per therm of natural gas. We can figure that out rather easily by dividing the amount that you paid by the amount of energy that you used. For electricity, the bill shows that we owe $145.95. If we divide that by the 1076 kilowatt hours we used, we find that we pay about 14 cents per kilowatt hour. We're going to discover what others pay in future lessons. Yet this is an important figure to note as it varies quite widely across the country and among countries. For natural gas, we owe $27.01 for the 21 therms that we used. And that comes out to be about a $1.29 per therm again, a number will look at later. But now, what do we do? Well, we have half the information we need, how much electricity and natural gas that we use to power and heat our home at least for the billing month in this case August. In order to determine our carbon footprint associated with our energy use. There is a little more work to do. We need to know where our electricity comes from, meaning how much of our electricity is generated using fossil fuels like coal or natural gas. But you've already done a lot of the hard part. So let's tackle that question, in our next lesson. We now know how much electricity we use to power our home. The next step in the process is finding out where that power comes from. As our carbon footprint associated with electricity depends upon the amount of fossil fuels used to produce all that electricity. As you can imagine, if all our electricity comes from coal will have a pretty large carbon footprint. If it all comes from wind power, will have a small or maybe even zero carbon footprint. In reality, your electricity comes from a mix of fossil fuels and renewables. And will be different if you live in Colorado, Illinois or anywhere else in the world. And that means your carbon footprint will depend on where you live. Fortunately for us, people have already figured out the mix of power generation technologies to use in all regions of the United States. And we're going to tap into those resources in our next lesson. The finish line is in sight, but there's still a little ways more to go. I'm Michael Reedy and I'll see you next time.
