I’m an engineer working on energy efficiency for buildings. Not a programmer. My start with AI was building small helper tools with Claude Code: pull weather or irradiation data from public sources, run some calculations, put out a clean report with charts and an export button. That works fine and I still use those tools daily. I use claude max20 and Opus. Where it falls apart is the next step up. In our projects we increasingly need to compare heating concepts: heat pump plus PV, gas vs. biomass vs. different heat pump types, with hourly profiles and price and CO2 factors per energy carrier. Nothing academic. I want a “good” solution, not the mathematically optimal one. As a rough yardstick for how deep this should go: in theory you could still build it in Excel. In practice Excel turns into a mess of switches once you add variants, which is why I’m doing it in code at all. The physics still has to be in there though: COP dropping with outdoor and flow temperature, PV yield by orientation and tilt, boilers cycling badly at part load. Output should be an HTML report plus an xlsx with the hourly series so my colleagues can check the numbers. Three things keep happening: Claude asks me questions I either can’t answer or whose importance I can’t judge, so I pick “(recommended)” and from then on I’m a passenger, not the driver. Example: I wanted a rough number for how much a buffer tank charged with surplus PV would help as a source for a water/water heat pump. Rough. Instead I got eight questions about port heights, flow rates and insulation values, two hours of code fixing, and a result that moved by 0.3 %. When I question an odd result, I get “You’re right, there was still a bug, fixing it now”, followed by long fix-and-verify loops that raise new questions, and the whole project spirals. Or it argues with my inputs: I told it the solar thermal collectors are tilted at 50° (I have photos of the roof), it kept asking whether 14° wouldn’t be more plausible given the yield data. The reports are full of what I’d call workshop talk: references to functions and files, simulation caveats in footnotes. My colleagues are engineers, not statisticians or coders. We end up with results none of us really feels in control of. I’ve tried CLAUDE.md, skills, custom commands. They’ve grown over time, often because Claude asked “should I add this to the global conventions?” and I said yes. I now suspect they’re too long, partly contradictory, not fully read, and not triggered where they’d matter. “Less is more” is probably the answer, but I don’t know what the lean version looks like for this kind of work. Every tutorial I find is written by devs for devs and I can’t translate it to my domain. So: anyone else using Claude Code as an engineer for simulation-type work rather than software? Is this a setup problem on my side, or is the tool simply made for writing code and I’m asking it to do something it was never meant to do? Happy to compare notes. submitted by /u/sharon__stoned
Originally posted by u/sharon__stoned on r/ClaudeCode