Thermostat disagreement with roommates

I’ve lived with my three roommates for three years now. In the past, we’ve had a few disagreements about the apartment thermostat, mainly in the summer and winter. For our first year, we lived on campus, so electricity was paid for and nobody cared much about what temperature the dorm was. The past two years, we’ve lived in an apartment where we do have to pay for electricity. I would like to keep the apartment comfortable while being as energy efficient as possible. We went through a period last fall where I would turn the air conditioner temperature up to something like 75 (the apartment didn’t get that hot often, so the a/c would only kick on if it got exceptionally hot) and they would turn it down to 70. This continued for a few weeks until it resulted in a huge argument where I didn’t talk to them or come out of my room much for a couple of days.
Now, it’s happening again. For the past two months, our power bill has skyrocketed $100 above what it has been consistently for the past two years. Our a/c has been set at 68 since spring. At first this wasn’t much of an issue, but I checked our city’s weather history and it hasn’t gotten below 68 once in all of July. The outside temperature got below 68 four times (at night) in all of June. So our air conditioner has been turning on and off constantly for two months, which explains the increase in power usage.
I am by far the most energy efficient roommate. I don’t say this out of pride, but out of concern that I’m paying more than my fair share of the power bill. While I have replaced the lights in my room with LED’s and this month my computer has used 30 kWh of our apartment’s 1700 kWh, according to my Kill-a-Watt power meter. One of my roommates likes to sit in the main room with the ceiling fan on watching videos on his Xbox all day long. At night he goes to his room, leaving the fan and sometimes the TV on in the main room, then watches TV in his room until he falls asleep, leaving the TV in his room on as well. Another sits in his room all day playing games on his Xbox One. All three of them are in the apartment much more often than I am.
None of this is an issue for them because their parents pay all of their living expenses. I, on the other hand, pay all of my own living expenses, and it’s a huge inconvenience to me to have to pay an extra $25 a month that I could be putting toward food or clothes or anything else. I know I probably just have to suck it up and pay the extra money until this school year is over, then move out and never live with them again. Still, I’d like to know if anyone can think of a more productive way to deal with roommates who don’t care about power usage. Any suggestions would be appreciated.

Tell them politely that there is a cap on what you can/will pay for electricity and they will need to cover the overage. Base the cap on previous average, reasonable bills.

Time to move out,sorry to say. It would have been best to resolve this last year.

I think that it should be 72 for summer and 68 for winter.
Good compromise.

It sounds like this has been an issue for years yet you continue to live with them. At this point assuming you want to stay together I’d sit down with your roommates and try to work out a compromise you can all live with.

Yes, it is time to move out. I would have been livid at 75 degrees (grumpy above 70) and leave the ceiling fans on all the time to help cool the rooms. As you have determined, you and the roommates disagree on what is comfortable, both with the temperature and the shared expenses.

You could consider the current extra expense the price of peace until you can move to a place where utilities are included or where you can live alone and control all electricity use.

My daughter has lived in an apartment with roommates for the past 2 years. One way she has avoided arguments is to have her own dyson fan heater to regulate her unshared bedroom.