Index
Questions
137 specific questions are published in this edition. The current inventory is fully written as pages.
Each published page is written to answer that phrasing directly, with a worked example or a dated table, not as a retitled copy of the overview. The sources page lists the methods behind the calculators.
Panel capacity and EV charging
Can a 100-amp panel support a Level 2 EV charger?Can a 150-amp panel support a Level 2 EV charger?Can a 200-amp panel support an EV charger and an electric dryer?Can I add an EV charger and a heat pump to a 100-amp panel?Can I add an EV charger and a heat pump to a 200-amp panel?Does my panel support an EV charger and a dryer at the same time?40 amp vs 50 amp EV charger: which circuit do I actually need?Do I need a 60-amp breaker for a car charger?Why is EV charging a continuous load, and why do electricians use 125%?What is a residential load calculation for an EV charger?Can I use 12 months of utility peak demand to see if I can add an EV charger?Load management vs a panel upgrade for an EV charger: which should I consider?Open breaker spaces vs service capacity: why can a panel look empty and still be full?Can a 100-amp, mostly gas-appliance house take a 32-amp Level 2 charger?Can a 100-amp panel with an electric range take a Level 2 charger?Will a 48-amp Tesla Wall Connector fit on a 200-amp panel?Should a Level 2 EV charger be hardwired or plugged into a NEMA 14-50 outlet?Can I plug an EV charger into my dryer outlet?My main breaker is 100 amp but the panel label says 200 amp. What does that mean?32-amp vs 48-amp EV charging: how much faster is the bigger circuit?Can a 125-amp panel support a Level 2 EV charger?Can a 100-amp panel support two EV chargers?Can a 200-amp panel support two EV chargers?Does a 16-amp Level 2 charger fit on a 100-amp panel more easily than a 32-amp unit?Can I add a 40-amp EV circuit to a 100-amp panel that already has a 40-amp dryer?Can I add an EV charger if my panel is already full of tandem breakers?What does “load calculation” mean on an EV charger permit?Can I use a 30-day recorded demand instead of 12 months of utility data?If I have rooftop solar, can I still use a measured-demand load calculation?Does a power wall or battery backup change my EV load calculation?Can a smart panel or energy management system let me skip a service upgrade?Do I need a permit to install a home EV charger?Outdoor vs indoor EV charger installation: what changes?How many miles per hour of charge do I get from a 32-amp vs 40-amp circuit?Is a NEMA 14-30 dryer-style outlet enough for Level 2 charging?Should I install a 14-50 now so I can take a faster charger later?Can I charge an EV and run a hot tub on a 200-amp panel?Can I add an EV charger to a subpanel in the garage?What size wire do I need for a 40-amp EV charger circuit?What size wire do I need for a 50-amp EV charger circuit?Does a Level 1 charger still need a load calculation?How do I find 12-month peak demand on my utility bill or portal?100-amp panel, electric water heater, and a 32-amp charger: will it work?100-amp panel with central air and a Level 2 chargerDoes an induction range change whether my panel can take an EV charger?Can I add a heat pump water heater and an EV charger on 200 amps?What is the difference between service amperage and panel bus rating?My lights flicker when the AC starts. Can I still add an EV charger?What does a panel schedule need to show for an EV permit?
Service upgrades and cost
How much does a 200-amp panel upgrade cost?What is actually included in a 100-amp to 200-amp service upgrade?Do I need to upgrade the meter base when I upgrade the panel?Can I add an EV charger or a generator to a fuse box?Is 200 amps enough if I have an EV charger and a heat pump?How do I read the amp rating on my electrical panel?Do I need whole-home surge protection when I upgrade the panel for an EV charger?How long does a 100-amp to 200-amp upgrade take, and how long is the power off?Who calls the utility for a service disconnect and reconnect?Does a Federal Pacific or Zinsco panel have to be replaced before an EV charger?Is a 200-amp upgrade enough for a future ADU as well as an EV charger?Level 2 EV charger installation cost if I don’t need a panel upgradeDoes a 200-amp panel upgrade add home value?100-amp to 200-amp upgrade cost in a high-cost city vs a national averageDo I need to replace the service entrance cable with a 200-amp panel?Can I add a 200-amp panel on a 100-amp meter and call it an upgrade?What permits and inspections are required for a service upgrade?Is a 400-amp or dual 200-amp service worth considering for EV plus heat plus an ADU?Should I upgrade to 200 amps now if I only need the EV charger later?What is a “heavy-up” in an EV charger quote?Can my insurer require a panel upgrade before they’ll cover an EV charger?Knob-and-tube or aluminum branch wiring and a new EV circuitHow do I compare three electrician quotes for a 200-amp upgrade?
Backup power and generators
Interlock kit vs transfer switch: what’s the difference?Manual vs automatic transfer switch: which do I need?Can I use an interlock kit with a portable generator?Is it safe to backfeed a generator through a dryer outlet?Do I need an automatic transfer switch for a standby generator?What size generator do I need for a refrigerator, a gas furnace, and some lights?What size generator do I need for a well pump and a refrigerator?What size generator do I need to run central air conditioning?Do I need a soft start to run my air conditioner on a generator?30-amp vs 50-amp generator inlet: which should I install?Portable generator with an interlock vs a standby generator with an automatic transfer switchCan a portable generator power a heat pump?Can I run an electric dryer on a portable generator?Where should I put a portable generator so carbon monoxide is not a risk?Whole-house vs essential-circuits generator sizing: what is the actual difference?Can I install an interlock kit on a 100-amp panel?Can I install an interlock kit on a 200-amp panel?Does an interlock kit meet code as transfer equipment?What size generator do I need for a sump pump, fridge, and furnace?What size generator do I need for a 10,000 BTU window air conditioner?Can I run a well pump, fridge, and lights on a 5,000-watt generator?Gasoline vs propane vs natural gas for a home backup generatorDo I need an inverter generator for electronics and a furnace board?How do I keep a portable generator from overloading when I use an interlock?Can I use a generator interlock and an EV charger on the same panel?What size standby generator do I need for a whole house with a heat pump?Is a 7,500-watt generator enough for a fridge, furnace, and a well pump?Do I need a building permit for a generator interlock and inlet?How far from a window does a portable generator need to be?Can I back up a gas furnace without backing up the whole house?
Heat pumps and operating cost
Heat pump vs gas furnace: which costs less to run?Is a heat pump cheaper to run than a gas furnace in California?Is a heat pump cheaper to run than a gas furnace in Washington or Idaho?Is a heat pump cheaper to run than a gas furnace in Massachusetts or New York?What is HSPF2, and why can’t I compare it directly with AFUE?What does a COP of 1.75 at 5°F mean on a cold-climate heat pump?Dual fuel: when would a heat pump switch over to a gas furnace?Ductless mini split vs a window air conditioner: what’s the real difference?What size mini split do I need?Do heat-pump backup heat strips mean I need a panel upgrade?Will installing a heat pump require a panel upgrade?How do I compare heat-pump running cost using last year’s gas bill?Will a heat pump work in a Minnesota or Wisconsin winter vs a gas furnace?Heat pump vs furnace operating cost in TexasHeat pump vs furnace operating cost in Illinois or OhioDoes Time-of-Use electricity make a heat pump cheaper than the EIA average suggests?How much backup electric heat will a cold-climate heat pump actually use?Mini split vs central heat pump for a house with existing ductsCan a ductless mini split heat a garage or a sunroom?How many BTU mini split for a 400-square-foot room?How many BTU mini split for a 1,000-square-foot open plan?Do I need a multi-zone mini split or several single-zone units?Will a mini split work in a cold climate as the only heat source?SEER2 vs EER vs CEER: how should I compare a mini split and a window unit?Does a heat pump qualify for a state or utility rebate in 2026?Should I replace a furnace and AC with a dual-fuel heat pump or a full electric heat pump?How do I estimate annual heating load from heating degree days?Is it cheaper to run a heat pump on a Midwestern utility than to run gas, using my actual rates?What HSPF2 should I look for if I live north of Region IV?Can I add a ductless mini split to a 100-amp panel?Does a heat pump raise my summer bill enough to cancel winter savings?What size heat pump do I need for a 2,000-square-foot house?Can I run a heat pump on off-peak electric rates and beat gas?How do I convert $/Mcf gas prices to $/therm for a furnace comparison?Should I keep my gas furnace as backup if I install a cold-climate heat pump?
A machine-readable inventory and source types are kept with the project (questions_inventory.json) and summarized in QUESTIONS.md.