Glad to hear about your commitment to utilitarianism!
I would note, re the camper van, that minimizing costs so that you can give more is only one part of the equation. There may be productivity costs associated with putting your own well-being at too low of a floor such that it may make sense to spend a bit more on yourself.
Getting used to a camper van may only make sense if you really plan to work in like SF tech where housing costs are out of control. Otherwise it makes a lot more sense to try maintaining a good relationship with family / friends, work on being a really good/easy room-mate, & then rent a cheap room from family/friends into adulthood to save more money.
I am writing a new years update on my efforts to be a full utilitarian, I am going to turn 15 in March (I am a freshman) and when I grow up I am going to donate everything to charity. Since I am trying to maximize my future income, I am currently at the best public high school in my state (magnet hs), and this is the happiest year I have had so far. My grades are pretty good, although it is very hard to get everything done in time. I have decided that it it actually quite unlikely that it is going to be utilitarian to work so hard I hate my life in the future, as that would require me to sacrifice sleep and other things which would cost years off of my lifespan that I could be working. However, I will still do things like living out of a camper van. I am doing 2 hours of track every day, which is pretty fun, I have a 5:49 mile now. I am also a life scout, and learning python. However, because it is unrealistic I make it into a college off of the basis of that, I will try to do pole vault as well. I also quit all junk food. However, now some personal things: I am literally more happy than I have ever been in my life. I find I am almost never mad like I used to be, and I am very rarely guilty or anxious, I am just happy most of the time. There are only a few people who live near me at my school, so what I am trying to do is set up something where I hang out with them every day after track to do hw for part of the time and hang out for the rest. I am also trying to not hang out with people who only go on their phones when they are with me as much. I also am going to try to get my GPA up to a 4 from a 3.75. I am realizing that although I am doing much better than most people, I can only compare myself to the best I can be. Next year, I am a bit worried because I have to take ap calculus and I don't know how hard that will be. I feel like anyone reading this would think I am extremely antisocial, which it obviously does sound like from everything I do, but it is not like that at all, I do have a lot of friends who I hang out with often. By the way, I will not communicate with whoever responds until I am 18 because they might be a pedo or something and their probably faking it, but I do want to see if there is anyone else who would want to live in a camper van with me when I get older, because it is obviously extremely rare to be a utilitarian and I can't expect that any of my friends or anyone I meet will be, and living alone in a literal camper van would cause a huge debt of social interaction, causing me to die earlier, be less happy, and possibly even go back on some utilitarian principles (like moving into an apartment or a house or smth) because of how much less happy I would be there alone. Now, despite the fact that that last part was kind of somber, things are going great in life right now. I'm happy, hope everyone reading this is too!
Hi! I'm a long time effective altruist (14+ years) and utilitarian/utilitarian-adjacent. This is a sweet and earnest post - you're clearly bright and I admire your dedication at such a young age. You're right to recognize that burnout isn't utilitarian, but I worry that your "donate everything / camper van" framing is premature and probably wrong.
At age 14/15, the highest-EV move is almost always building optionality, not making binding commitments to extreme frugality. You're right to maximize income, but I think you're thinking too much about this in terms of "save money" and not enough in terms of "earn more money". Your comparative advantage at 14 is completely unknown. You might become a researcher, policy person, entrepreneur, or earn-to-give - these all have very different optimal life strategies. And your ability to find and execute on the best path, and do that path well, will certainly lead to higher impact in the long-run than self-sacrificing immensely right now. I think moving into an apartment or a house is compatible with being a utilitarian. For example, Peter Singer lives in a house, as did a lot of other historical utilitarians.
Also... "Living alone would cause a huge debt of social interaction, causing me to die earlier" is... technically true but also a somewhat alienating way to think about relationships? Friends aren't just longevity inputs. Be careful not to instrumentalize everything - that path leads to feeling disconnected and often to abandoning the whole framework.
Advice I'd give:
Yeah, the cost of cheap shared housing is something like $20k/yr of 2026 dollars, whereas your impact would be worth a lot more than that, either because you are making hundreds of thousands of post-tax dollars per year, or because you're foregoing those potential earnings to do important research or activism. Van-living is usually penny-wise, but pound-foolish.