Case study 4: Dallas, Texas.

Start with a carbon budget of 3000 lbs of carbon per person per year. 1000 lbs is taken up by unavoidable supply chain stuff for food, clothes, etc. just to survive, assuming they mostly buy local food. Now we have 2000 lbs of carbon to use as we wish. Can we make this work?!?

Dallas is a large city of about 1.4 million residents in the city proper, but is part of a metro area of over 7.5 million people. The city has a very diverse economy, with an average income of about $26,432 per capita compared to a US average of about $31,786. The climate is hot in summer, usually in the 90s, with medium humidity, and winters are mild, with some freezing weather and occasional snow. There are 234 sunny days per year in Dallas, making it a good place for solar power. The city is about 300 miles from the ocean. Ranching continues to be a big part of Dallas county, with about 50,000 head of beef and dairy cattle. Dallas averages 37 inches of rain per year, so it should be possible for them to develop more plant agriculture in the area as well.

Because Dallas proper is spread over 385+ square miles, commutes and running errands are a challenge. Dallas workers commute an average 24 miles round trip every day. https://www.bizjournals.com/dallas/news/2018/12/07/north-texas-that-commute-is-going-to-cost-you.html

The transit system, DART, operates buses and commuter rail covering 13 cities and 700 square miles! 649 buses carry about 88,000 individual rides per day. That comes out to 135 rides per bus per day, so I’m sure the buses aren’t super full most of the time (another 82,000 rides per day on the commuter rail = only 85,000 people are riding the bus and train round trip per day, or less than 6% of the population). It still saves a great deal of metal, gas, and road room over having each of those people drive a car and the good news is they have a lot of capacity to carry more riders in comfort! They also have a light rail system that carries 30 million passenger trips a year.

OK, now to the scheming!

Let’s assume they walk about a quarter mile a day total to and from the buses and commute by bus 24 miles a day. A 24 mile commute is way too far for all but the toughest to commute by bicycle. Assuming regular 5 day work weeks and 50 weeks of work a year, that equals 6000 miles of commuting by bus. Let’s add in another 25 miles a week for your shopping and socializing, so another 1300 miles. The commuter rail is awesome, but as it is fixed we will be focusing on buses, which are easier to adjust in response to customer demand.

We now have 7300 miles of bus commuting per year. At 0.25 lbs of C02 per mile, that is 1825 lbs of carbon emitted per person.

We have used 1825 out of 2000 lbs of carbon already!

Priority 1 for individuals in Dallas might be to move closer to work or change jobs.

The biggest challenge for Dallas as a city is probably creating their own farm belt around the city to produce local food instead of importing their food thousands of miles, next limiting further urban sprawl, and then dealing with the food deserts in some neighborhoods where there aren’t enough proper grocery stores. http://greendallas.net/food/challenges

Another thing Dallas should do as a city is lower their average summer temperature, and air pollution, by making sure there is around 40% tree cover throughout the city. https://www.mnn.com/earth-matters/climate-weather/blogs/trees-are-not-so-secret-weapon-keeping-our-cities-cool Instead of, say, 90 degrees in June, you’d have only 85 degrees at 4 p.m. This would not only make commuting more pleasant but also reduce the amount of air conditioning needed by quite a lot.

Baseline electrical usage per house:

Multiple house lights, CFL 200 wh

2 smartphones 11 wh a day to recharge

1 laptop or desktop 200 w, 60 min/day at 200 wh

1 tablet 50 wh

2 TVs (200 w each) 5 hours a day each at 2000 wh

1 game console 50 w 2 hours a day at 100 wh

Coffee maker 1500 w, or 500 wh

Microwave 1500 w, or 50 wh

Mixer 125 w or 25 wh

Garbage disposal 500 w or 50 wh

Slow cooker 200 w, or if used twice a week for eight hours, average 500 wh

Curling iron 90 w, 45 wh

Shaver 25 w, 5 wh

Hair dryer 1500 w, 250 wh

Wifi 24 w x 24 580 wh

Dryer 2000 w 1000 wh

Washing machine 500 w 300 wh

Vacuum 200 w, or 50 wh

Chest fridge 100 wh https://mtbest.net/chest_fridge.html

Chest freezer 1000 wh

Well insulated water heater 2500 w for 2 hours so 5000 wh

Baseline: 12016 watt hours or 12 kwh per day.

AC 5000 w, or average out 1 hour on during winter and 6 hours on during summer, 17.5 kwh. I’m going to vote for air conditioner rather than evaporative cooler on this one due to higher humidity levels.

Total: 29.5 kwh a day.

Using 100% solar power, this would equal 45 oz of C02 per day, or 1027 lbs per year. Since average household has 2.5 people, you will have to make your own calculations, but strictly on math, that is 411 lbs per person per year.

We are now running over budget by 236 lbs. Uh-oh. And that doesn’t even really leave room for fun things like vacations.

Let’s go over the numbers again and see what we can change. Let’s not adjust how much you use your appliances and gadgets – we’re trying to make this comfortable and as easy as possible, not deal with hardship.

Some options –

You can move closer to work – or change jobs. Each mile closer to your work saves you 125 lbs of carbon a year. If you shave off 10 miles you can fly 2000+ miles for vacations every year.
If you have no children in the house, enough bedrooms, and want some extra money, consider renting out your rooms. Not only will you make extra money, you will cut way down on your share of the house’s carbon footprint, as it costs the same to heat or cool a house with 1 or 4 people in it. If you get three people per house and have solar installed (or buy green energy) then your carbon footprint from the house will only be about 292 lbs a year. Four people and you get it down to 257 lbs, which puts us over budget by only 82 lbs.
Let’s look at the commute again. What if you arrange a carpool using buses to meet up, at least some days of the week? Both solar electric and hybrid cars give off about 0.50+ lbs of carbon per mile. If you have 5 people in the carpool three days a week and the carpool takes you just half of your commute (12 miles round trip) then that equals 1800 miles a year at just 0.10 lbs of carbon instead of the bus’s 0.25 lbs. You saved 270 lbs of carbon and hopefully made or deepened friendships as well in that time. Loneliness is a huge problem in modern America, so this might turn out to be a ninja trick to make your mental and emotional health way better.
Or, you could try replacing your air conditioner with an evaporative cooler when it inevitably wears out and perhaps install a window AC unit in bedrooms to ensure nights are always cool even when humid. Savings on this one are bit harder to add up, but it would help.

These are just some ideas. People are nothing if not creative, so have fun figuring out your own solutions!