How to Reduce Emissions

This page was put together by the ZEN team to use as a resource on ways to reduce your carbon emissions. From transportation to energy to your diet, we’ll give you the facts and some tips on how to reduce your carbon footprint.



Transportation accounts for approximately 430,392 metric tons of CO2 equivalent emissions, which is 28% of all greenhouse gas emissions in Boulder. If nothing is done about our emissions from transportation, its share of Boulder’s overall emissions will rise quickly as our power grid improves. When we say “emissions from transportation,” we are referring almost exclusively to on-road fuel emissions from cars.  Every day in Boulder, tens of thousands of cars come in and out of Boulder for work, but there are other options. Boulder has a well-planned public transit system made to counteract this. Public transportation extends out to nearby towns to allow people to avoid the morning traffic and keep some emissions off the road. Also, you may have heard about electric cars, but we went in depth to give you the information you need before considering one.


In Boulder, transportation, which refers mainly to car travel, accounts for over 28% of GHG emissions.

The modern world absolutely relies on vehicles for many aspects of life and this is proven by the more than 1 billion cars that are currently on the road. Unfortunately, internal combustion engine vehicles (ICEVs) are known to be large emitters of carbon and other harmful gases. Using average miles per gallon and average mileage per year data, the average ICEV emits around 4.53 metric tonnes of CO2 per year. To put that number into perspective, it is the equivalent amount of pollution to running a standard 9-watt LED light bulb for 97 years or leaving on a 32″ flat screen TV for about 17.5 years. And that is just one car! Now think about 1 billion cars!

There are some very effective ways in which we can reduce our pollution from transportation sources. The main thing is just to drive less. One option is to carpool. Approximately 46,000 vehicles travel in to Boulder every weekday morning. It’s estimated that around 75% of those have only one occupant each. Another option is to take public transportation. Boulder has a well-structured public transit system built to help commuters get to work from surrounding cities and many routes are available within the city. Just think about how much you pay in gas each week to drive yourself into Boulder.

Electric vs. Internal Combustion Comparisons

Reducing the amount of driving that you do sounds great on paper, but we understand that it’s much easier said than done. Luckily, there are other ways that you can reduce your footprint and still do all the driving you want, and you might save some money.

Here I’m going to get into some of the nitty-gritty numbers that tell you why it might be worth it to invest in electric. It is important to keep in mind that many of the numbers below are subject to changing over time; all calculations were done with the data available in December 2019.

  • Using the average ICEV miles per gallon (25.2), the average gas price in Boulder ($2.75/gallon), and the average cost of electricity ($0.11/kWh), we calculated that a 350-mile-range gas tank costs about $38.19 to fill, while an EV with 350 miles of range costs about $13.20 on your electric bill. That’s about $25 of saving per full charge.
  • On a yearly scale, the average person drives 13,476 miles per year according to the Federal Highway Administration. This adds up to $1470 in refuels for an ICEV in a year. On the contrary, recharging your EV would cost only $508 per year, a savings of around $962 in a year and almost $10,000 in ten years.
  • EV’s have far fewer moving parts compared to ICEV’s, meaning that they require maintenance far less often. An in-depth study from the peer-reviewed “Energy Policy” journal looked into the price savings of an EV vs an ICEV just from maintenance. This study even takes into account the decreased time value of money ($10 now is worth more than $10 in 10 years), so keep in mind that the true numbers are even higher. The study found that the average maintenance cost for an ICEV is $5,821 over 12 years while the cost for an EV is $2,490 in 12 years. That’s another $3,331 over 12 years plus no annoying trips to get your oil changed.
  • The last important factor is the government subsidies that are offered right now for buying an electric vehicle. Because the federal government and the State of Colorado realize how important it is to switch to electric vehicles, they are currently offering subsidies of $7,500 federally and $5,000 through the state. These subsidies are changing constantly so be sure to check out the current numbers.
  • Over 10 years, that is savings of around $10,000 from electricity vs. gas, ~$3000 from maintenance, and $12,500 from government subsidies. That’s over $25,000 in 10 years… enough said.


Considering the immense amount of pollution that is created by relatively small cars and other ground vehicles, it make a lot of sense that airplanes are significantly worse. Airplanes are far less abundant than cars and don’t contribute as much to the total human impact, but they are still a large concern that should be addressed.

According to the International Energy Agency, “Air travel contributes about 1 gigaton of CO2 to the Earth’s atmosphere each year.” To put 1 gigaton into perspective, that is about 2.5% of yearly global CO2 emissions. Below, we have compiled some statistics from the National Air Traffic Controllers Association and the Federal Aviation Administration:

  • One average day in the US alone sees around 87,000 flights
    • Around 90% of these flights are passenger flights, both commercial and private
    • Less than 10% are cargo flights
  • There are over 16,000,000 commercial flights each year in the U.S. (nearly twice that if you include private and other flights)
  • Over 1,000,000,000 passengers fly yearly
  • Around 44,300,000,000 pounds of freight is flown each year
  • Around 18% of seats on passenger flights are unfilled

Around 70% of an airplanes exhaust is comprised of CO2, around 30% is H2O, and the other less than 1% include pollutants such as methane, nitrogen oxides, sulfur oxides, and more. All of those pollutants are greenhouse gases that are linked to climate change and contribute to worsening air quality.

As easy as it would be to simply recommend that you should just stop flying in planes if you can (which we do recommend), we also understand that flying is an integral part of modern society and people need to fly to travel long distances. Here are our recommendations:

  • The best thing that you can do to reduce your emissions from flying without changing your flight habits is to try out a flight-offset program. To learn more about some of these programs and what they entail, check out our solutions page!
  • When possible, look for nonstop flights as opposed to flights with layovers. Most people probably try do this anyway for convenience’s sake, but takeoff and ascent contribute by far the most to the energy usage of a flight, above 75% of energy usage on a short flight.
  • Try to avoid short flights if possible. Since the takeoff is the worst-emitting part of the flight, it is likely that other forms of ground travel will be less impactful than taking a short flight.
  • Stick to economy-class seats.
    • Economy seats are smaller, meaning that more passengers can fit in each plane.
    • Lie-flat, first-class seats can be up to 4 times more energy-intensive than economy ones.
    • Vote with your dollar; it is important to show airline companies that we don’t want more planes with fewer seats – instead, we want more people per flight.
  • Carry less/lighter luggage. The heavier your luggage is, the more energy it takes to move it.


Home Energy


The next big slice of Boulder’s emissions pie comes from residential, commercial, and industrial energy usage. Residential greenhouse gas emissions contribute around 17% of Boulders total emissions, commercial/industrial emissions represent around 54%. Energy used in Boulder to heat and power buildings accounts for 71% of GHG emissions. These emissions from energy generation are a direct consequence of Xcel energy’s mostly non-renewable resource usage. As Xcel energy improves the energy grid by using more renewable options, Boulders emissions from residential and industrial energy uses will decrease. To learn more about Xcel Energy and the energy grid, check out our Local Government and Grid page.

In this section, we will talk about the areas of peoples homes that use the most energy and increase emissions. Even though industrial/commercial emissions are much higher than residential, the average person cannot do much to affect those emissions, but everyone can work to reduce the emissions from their home.


Home Heating

For the average household, around 45% of your energy bill comes from space heating. Over 50% of the energy needed to heat your house comes from natural gas and all together, heating your house contributes over 32 metric tons of CO2 equivalent each year (112,913 bathtubs of CO2). The statistic that might hit home the hardest is the average U.S. household spends around $700 per year to heat their home using natural gas.

People will always need continue heating their houses and until the grid improves, emissions from home heating will never hit zero, but inefficient practices often lead to over usage of heating and an increase on the energy bill. Each degree of heating on a thermostat contributes more towards your emissions and your energy bill than you probably realize. Often times, simply being conscious about how much heating you are using is the best way to reduce your usage. Activities such as heating rooms that you are not using (the basement is a common culprit), leaving the windows open at night, closing the drapes on a sunny day, often contribute significantly towards heating your home unnecessarily.

Water Heating

Water heating is the second largest greenhouse gas generator for the average household. The average house contributes around 0.41 metric tons of CO2 equivalent (1421 bathtubs of CO2) to the atmosphere from water heating each year. This adds up to annual spending of around $500 each year.

The main cause of high emissions from water heating is typically just an old or inefficient water heater. The average water heater lasts around 8-12 years, it is common for homeowners to not realize they are overdue for a new one and continue using an old, inefficient water heater. We urge people not only to check if they are due for a replacement, but also to shop around for the best, most efficient fit for their home. Try using some of these resources to help find the best option, we recommend a solar water heater to avoid reliance on the grid as much as possible:

  • EnergySmarts: This company will help assess what water heater could be best for you by doing home energy audits. This company will also help you install a water heater. Also a great resource for solar panels, electric vehicles, and more!
  • XcelEnergy: Offers rebates on energy efficient water heaters
  • Elevations Credit Union: In conjunction with the Clean Energy Union, they offer low interest rate loans for water heaters

Home Cooling

The final major source of home energy usage comes from home cooling using air conditioning. Cooling only accounts for around 6% of home energy usage, significantly less than heating. Typically, the biggest reason that households have high emissions from their air conditioning is simply because they have a low efficiency air conditioner. You can reduce air conditioning energy use by 20-50% simply by switching to a high efficiency air conditioner.

The most important thing you can do to ensure that your current air conditioner is working efficiently is to regularly clean and replace the filters. If left uncleaned, this can also be a fire hazard. Other tips to improve efficiency include opening the windows instead of using the AC, make sure to not do both at the same time as this can waste even more energy. Make sure that your house is insulated properly, this means all doors and windows are sealed when shut, most importantly the attic and basement. Additionally, be sure to only cool the rooms of your home that you are using, the top floors of the house naturally get hotter and take more energy to cool, if you are not upstairs, don’t cool it, this will save you money as well.

Our Suggestions to Reducing Energy

Below is a list of the best ways to reduce your home energy usage. This is one of the areas of energy usage where most people have the most control of their activities. As is the case in other areas, the main thing that you can do to keep your home energy usage low is simply just to be conscious.

  1. Replace light bulbs 
    • Change your light bulbs to LED. On average, LED light bulbs use 75-80% less energy and can last ten time as long 
  2. Unplug appliances when not in use or use smart power strips 
    • Your appliances still use energy even when turned off. Ghost energy can account for as much as 10% of a home energy bill.
  3. Use a programmable thermostat 
    • A programmable thermostat can be programmed to turn off heating and cooling at certain times of the day. Such as when you are away. A programmable thermostat can save homeowners on average $150 per year on their energy bill. 
  4. Upgrade to efficient appliances
    • Appliances can account for up to 15% of a home’s energy usage.  When shopping for new appliances look for the energy star label. 
  5. Reduce hot water consumption
    • If buying a new water heater is out of your budget, you can still reduce hot water usage. You can turn down the thermostat on your water pipes, or isolate your water heater and pipes. 
  6. Replace windows
    • Install energy efficient windows. Windows are the largest source of heat escape in the house. To save on your energy bill you can replace your single pane windows for double pane ones.
  7. Upgrade your home’s HVAC system
    • Heating, ventilation and air conditioning can make up 40% of the home’s energy usage. An energy star certified heating unit can lead to major savings on your energy bill. 
  8. Weatherize your home 
    • By weatherizing and sealing air leaks around the home you will greatly reduce wasted energy. Find out how to weatherize your home here.
  9. Replace on insulation
    • Insulation plays a crucial role in reducing energy waste.  Find out how and what insulation is best to use here.

Diet and Animal Agriculture


In the US today, industrial animal agriculture is one of the largest contributors of greenhouse gas emissions and its methods are some of the most inhumane that we see anywhere on the planet. Whew, now that’s a bold opening statement, don’t worry too much though it’s not all bad. This section will be broken up in the same ways as before. First, we must discuss the negative aspects of industrial agriculture and our current diet habits. After that, we will dive into the positives and what people like yourself can do to improve, both in your own life and for the world.

Scattered throughout the information below are graphics detailing some of the effects and the emissions of different foods.

Carbon Emitting Activities

Confined Animal Feeding Operations CAFO’s

When we say, industrial agriculture, we are largely referring to Confined Animal Feeding Operations (CAFOs). Livestock farming in the U.S. has shifted from small, family farms to large, corporate factory farms. Today, 99% of meat is produced in CAFOs while only 1% is raised on ‘humane’ farms. New technology has enabled farmers to increase efficiency and lower costs, so more profit can be made with less land and capital. The agricultural system currently rewards big farms with low costs, so size continues to increase.


A CAFO is a facility where animals are confined and grown for 45+ days a year, and no vegetation is allowed to grow. They contain more than 1,000 animal ‘units’ and produce waste that enters the water supply. Animal products including beef, veal, dairy, eggs, poultry, pork, lamb and more are produced in CAFOs.


Each CAFO can produce millions of tons of manure annually sometimes creating more waste than entire cities – and this waste must simply “go to waste” since there’s no need for fertilizer on the livestock farm. The manure can contain nitrogen, phosphorus, E. coli and other pathogens, hormones, antibiotics, chemicals, blood, silage leachate from feed, and copper from cow footbaths. Manure is often applied to the soil, but over application frequently leads to nutrient runoff and leaching into groundwater. In dairy and hog CAFOs, anaerobic or manure lagoons – outdoor basins filled with waste undergoing anaerobic respiration, which are often left untreated – can become overwhelmed and overflow. Excess manure and storage malfunctions lead to polluted ground and surface water.

On dairy farms, 150 gallons of water are used per cow every day. This water is just used to wash away waste – the majority of water used by factory farms isn’t for the animals, it’s for cleaning and processing animals during slaughter.

CAFOs also release 168 types of gasses, emissions from manure and livestock digestion pollute the air in neighboring communities and around the globe. Livestock production is responsible for 14.5% of global greenhouse gas emissions, according to the United Nations’ Food and Agriculture Administration, and therefore it contributes heavily to climate change.


According to World Wildlife Fund, overfishing is one of the main reasons why ocean wildlife is suffering and has declined by 50% over the last 50 years. Overfishing occurs when fish are caught faster than stocks, or fish populations, can restore themselves. The quantity of overfished stocks has tripled over the last 50 years and 1/3 of global assessed fisheries are exceeding their limits. A fishery is a fishing ‘ground’ or area where fish are caught.

Furthermore, overfishing is often accompanied by bycatch – when unwanted sea creatures are also caught while fishing for another species. Bycatch wastefully kills billions of fish, and hundreds of thousands of other species like sea turtles and marine mammals, every year. Not only is overfishing ecologically destructive, it depletes the source for the billions of people who depend on fishing for food, and the millions who depend on fishing as a livelihood. Overfishing is largely the result of poor fishing
– most fisheries have little to no rules and regulatory enforcement to ensure the health of the fish populations.

In addition, working conditions for fishermen are frequently inhumane – in Thailand particularly, slave labor in the shrimping industry has recently become a major area of concern.

Deforestation & Land Conversion

Deforestation for the sake of converting land for agricultural purposes, be it pastureland, cropland, or plantation, is one of the leading causes of agriculture’s carbon dioxide emissions. Animal agriculture, specifically, is
responsible for about 1/3 of biodiversity loss because it is one of the largest causes of global deforestation. About 75 percent of historic deforestation in the Brazilian Amazon Rainforest alone, is due to livestock production.


Carbon Reducing Activities


To restate what should now unfortunately be obvious, the global food industry is a major source of concern for animal rights and for carbon emissions. But actions can and are being made to help, that’s why we are here! A good knowledge of the industry and of your local resources is the most important first step toward helping the planet and yourself. Now I will leave it to our diet and agriculture specialist, Ellie, who has so elegantly explained what the following section will include:

As we each try to tread more lightly on the planet, food is an essential ritual in our lives through which we can reduce our carbon footprint and our production of waste; and through which we can heal our ecosystems, our communities and ourselves. By engaging with local producers, vendors, and organizations, we can make strides in sustainability while empowering farmers and enriching our own lives. We hope to provide you with information and the local resources that you need to take action in the aspects of your diet that matter most.

Animal Agriculture

Small-scale and regenerative farms that integrate livestock with farming, in contrast to CAFOs, can greatly benefit our ecosystems and farming operations. Livestock helps to recycle nutrients in the soil, maintain soil structure and water retention, and can reduce labor needs on the farm. Manure from livestock provides fertilizer for crops, and animals like goats, sheep, cows, and even ducks are great at keeping unwanted vegetation and bugs at bay. 

When you know where your meat, dairy and eggs are coming from it is much easier to ensure the humane treatment of farm animals. Small farms do not operate on an industrial scale and must tend to the health and well-being of livestock, individually caring for each animal for the duration of its life. Healthy animals produce healthy food.


Seafood from sustainably-managed fisheries and farms can be a valuable source of healthy protein. Unfortunately, it can often be hard to tell where seafood products come from and if they’re actually responsibly harvested. While issues are prevalent in the seafood industry, “eco-labels” are a tool to make it easier for consumers to choose sustainable, ethical seafood at the grocery store. Eco-labels use a rubric to assess the environmental impacts of wild fisheries and aquaculture. Wild fisheries are assessed on how abundant certain fish are, how and where fish are caught, and if fishing gear is harmful for marine life. Aquacultures are assessed on their location (on land, in a river or in the ocean), what type of feed is used, if pesticides or antibiotics are used, and how often farmed fish escape the aquaculture.

Only 14% of fisheries are sustainably certified, and it is a complex process to determine if fisheries deserve certification, as well as what type of certification. Not all uncertified fisheries are necessarily unsustainable, and similarly, many certified fisheries could still improve their ethical or sustainable practices. So even though eco-labels are a work in progress, they can still be useful in consciously narrowing down our seafood choices. Another way to sustainably consume seafood is to choose specific seafood products that are more sustainable, rather than focusing on eco-certification labels. Some species are more locally abundant or sustainably caught than others. Below is the Monterey Bay Aquarium’s Seafood Watch guide to the species that are best to consume if you live in Colorado:

Palm Oil

Like seafood, there is a certification for sustainably-grown palm oil. As with any certification, there is speculation about the efficacy of eco-labels and authenticity of sustainable management, and of course there is always plenty of room for improvement on both fronts. Because palm oil is in the vast majority of food, beauty and household products, it can be challenging to avoid. The RSPO (Roundtable on Sustainable Palm Oil) Certification can be a useful tool when making purchasing decisions, as it tries to distinguish certain products/brands based on eight RSPO principles meant to ensure good environmental, social and economic practice. If you are able to, look for the RSPO certification on packaged goods. Palm oil is not always clearly labeled on products, so you might think a good is free of palm oil when it’s really just listed under another name. Below is a chart of all the alternative labels that palm oil may be hidden as in your ingredient list:


Food Miles

Perhaps contrary to popular belief, the transportation of food usually does not significantly impact the carbon footprint of what we eat. About 60 percent of global food miles come from transport by sea, while 30 percent is due to transport by road, 10 percent by rail, and 0.16 percent by air. Because such a small amount of our food travels by plane, the benefits of eating local have a greatly reduced impact on agricultural transport’s carbon emissions. While few foods take flight to reach your grocery store, those that do come with consequences for the climate. Transporting food by air produces fifty times more greenhouse gas emissions than transporting food by sea. Foods that are commonly transported by air are highly perishable imports, like green beans and grapes.

How do you know what foods you normally buy flew to you? These goods aren’t labeled by what mode of transportation they took. A general rule to live by: if a food is highly perishable and was grown far away, it was likely flown.

Local Farm Highlights

Cure Organic Farm: 7416 Valmont Road, Boulder, CO 80301

Cure is just east of Boulder, and grows over 100 kinds of organic vegetables, herbs and flowers. The farm offers a CSA program and on-site farm store, and supplies local restaurants and farmer’s markets. They also raise pigs, laying hens and geese, and source grassfed beef from Homestead Natural Beef. Cure explains that their animals, “have names and personalities and are truly loved by our crew.” They additionally have education opportunities and community events.

  • Black Cat Organic Farm
    • 1964 13th Street, Boulder, CO
    • Black Cat produces food for its restaurants, farm dinners, CSA program and farmer’s market booth. The farm focuses on heirloom and heritage crops, and prioritize the flavor of their produce. They also grow many types of grain, and raise sheep, pigs, chickens, and geese on pasture and vegetable fields with holistic pasture management, “and lots of love and care.” You can also stop by their farmer’s market booth for recipes, cooking tips, and stories from the farm.
  • 63rd Street Farm
    • 3796 63rd Street, Boulder, CO 80301
    • 63rd St, is located near downtown Boulder and has a CSA program that includes organic produce, free range eggs, chickens, grassfed lamb and beef, and pasture-raised pork. The farm also has a future aquaponics center and a vineyard. 63rd St. also hosts Seed-to-Table dinners, culinary and permaculture design classes, and other events. They additionally sell medicinal herbs, and the fresh produce share options range from single-person to 3-to-5 person allotments.
  • Light Root Community Farm
    • 7715 Arapahoe Road, Boulder, CO 80303
    • Light Root is a “horse-powered” farm that offers dairy and fresh produce in the heart of Boulder. They practice biodynamic agriculture and are on “a path that works to enliven the Earth through our conscious land stewardship, reverent animal husbandry, and life promoting farming practices.” Their cows are rotationally grazed on grass pastures and supplemented with grass and alfalfa hay. They live outside year round and are milked once a day. The farm also hosts educational programs and started LEAF (Living Earth Agriculture Foundation), a 501-c3 nonprofit.
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