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EV Charging Calculator

Estimate EV charging time, kWh drawn, electricity cost, and rooftop solar savings. Free EV charging calculator using current 2026 U.S. utility rates.

EV Charging Calculator

Energy drawn from the source
50 kWh
Time to reach target
4 h 21 min
Cost on grid only
$8
Cost after solar offset
$4
Saving from solar: $4
Level 1 (1.4 kW): overnight only — adds ~5 mi/h.
Level 2 (7-11 kW): full home charge ~6-10 h.
DC fast (50-350 kW): 20→80% in 20-45 min, tapers above 80%.

How to use this calculator

Enter six numbers and the calculator returns the energy drawn from the wall, the time to reach your target state of charge, and the cost both with and without solar offset:

  1. Battery capacity (kWh) — the usable battery on your EV. 2026 mainstream EVs cluster around 75-85 kWh (Tesla Model 3 Long Range 75, Ford Mustang Mach-E ER 91, Chevrolet Equinox EV 85, Hyundai Ioniq 5 84). Pickups are larger: Ford F-150 Lightning ER 131 kWh, Rivian R1T 135 kWh, Silverado EV RST 200 kWh.
  2. Charger power (kW) — what your charging hardware actually delivers. Level 1 (120 V, 1.4 kW) wall outlets are emergency-only. Level 2 home chargers ship at 7.7 kW (32 A / 240 V), 11.5 kW (48 A), or 19.2 kW (80 A); the JuiceBox 40, Tesla Universal Wall Connector, and Wallbox Pulsar Plus are the U.S. mainstream. DC fast chargers run 50-350 kW at public stations.
  3. Starting and target state of charge (%) — most owners cycle 20→80% to preserve battery life. Daily driving rarely needs 100% — Tesla, Ford, GM, and Hyundai all recommend 80% daily.
  4. Electricity tariff per kWh — your residential rate in dollars. The 2026 U.S. average is $0.16/kWh (EIA Form 826). California PG&E EV2-A super off-peak: $0.27, peak $0.62. Texas Oncor avg: $0.13. Florida FPL: $0.13. New York Con Ed: $0.27.
  5. Share covered by solar (%) — the fraction of the charge offset by your rooftop array. With NEM 2.0 and a south-facing array sized to annual EV consumption, this is effectively 100% on an annual-credit basis. Direct-overlap (charging during daylight hours only) is typically 30-50% for a commuter who plugs in after work.
  6. Charging efficiency (%) — the wall-to-battery efficiency. Default 90% for AC Level 2. Use 93% for DC fast.

How the math works

The calculator uses standard energy-balance math:

energy_to_battery (kWh) = battery_kwh × (target% - start%) / 100
energy_drawn (kWh)      = energy_to_battery / efficiency
charge_time (hours)     = energy_drawn / charger_kw
grid_cost ($)           = energy_drawn × tariff
solar_savings ($)       = grid_cost × (solar_pct / 100)
final_cost ($)          = grid_cost - solar_savings

Worked example for the en-us defaults (75 kWh battery, 20→80%, 11.5 kW, $0.16/kWh, 50% solar offset, 90% efficiency):

  • Energy to battery = 75 × 0.6 = 45 kWh
  • Energy drawn from wall = 45 / 0.90 = 50 kWh
  • Charge time = 50 / 11.5 = 4.35 h ≈ 4 h 21 min
  • Grid cost = 50 × $0.16 = $8.00
  • Solar savings = $8.00 × 0.50 = $4.00
  • Final cost with solar = $4.00 per session

Over 12,000 miles/year at 4 mi/kWh, you’ll draw roughly 3,000 kWh annually for charging. At $0.16/kWh that’s $480/yr grid-only, or $240/yr with 50% solar — $4,800-7,200 saved over 10 years versus a 30 mpg gasoline car at $3.50/gallon ($1,400/yr in fuel).

Level 1 vs Level 2 vs DC Fast — what each is good for

Level 1 (1.4 kW, standard 120 V outlet): Adds about 4-5 miles of range per hour. Acceptable for plug-in hybrids and short-commute (under 30 mi/day) BEVs. Not viable for daily 50+ mile drivers.

Level 2 (7.7-19.2 kW, 240 V dedicated circuit): The U.S. mainstream. A 48 A / 11.5 kW unit on a 60 A breaker fully refills any current EV overnight. Code reference: NEC Article 625 (Electric Vehicle Power Transfer System) plus 625.42 sizing rules — the circuit must be sized to 125% of the EVSE continuous load.

DC Fast (50-350 kW): For road trips and apartment dwellers without home charging. 350 kW Tesla V4 Supercharger and Electrify America Hyper-Fast stations charge a Lucid Air Pure or Hyundai Ioniq 6 from 10% to 80% in 18-22 minutes. Cost is 2-3× home charging. Frequent DC fast charging accelerates lithium-ion calendar aging — most studies show 5-15% additional capacity loss over 100k miles vs. a Level-2-only baseline.

Pairing EV charging with rooftop solar

Combining a residential solar array with EV charging is the single most-valuable use case for residential PV in the U.S. — the marginal kWh you self-consume is worth your retail rate ($0.13-0.55/kWh) instead of NEM 3.0 export credits ($0.05-0.10/kWh).

Sizing rule of thumb: add 1 kW of PV per 4,000 EV miles per year. A typical 12,000-mile driver needs roughly 3 kW of additional panels (about 7-8 modules, 350-400 W each) on top of household-only PV. The solar panel output calculator computes the per-state production figure.

For peak solar offset, schedule charging via the OEM app (Tesla, Ford, GM, Hyundai) or smart-charger software (JuiceBox, Wallbox) to start at 10 AM and end at 4 PM on weekends. Workday charging requires either daytime charging at the office or net-metering credit recovery overnight.

What changes the math

Lowers the cost (good)

  • Time-of-use plans — PG&E EV2-A, SCE TOU-D-Prime, ConEd Voluntary TOU, Eversource MA Active Demand cut overnight rates 30-60%
  • Bigger rooftop array sized to annual EV consumption (NEM 2.0 grandfathered states)
  • Battery storage paired with solar (NEM 3.0 California) to capture daytime PV for overnight charging at retail rate
  • Federal IRA Section 30C — 30% credit on home charger installation up to $1,000 (rural/low-income census tracts only after 2024)

Raises the cost (bad)

  • Demand charges in IID, SDG&E EV-TOU-5, and a handful of municipal utilities — kW-based fees that punish high-power Level 2
  • Tier-3 retail rates above 130% of baseline allowance (PG&E, SCE) at $0.40-0.62/kWh
  • DC fast as a daily habit — adds 30-50% to per-mile cost and accelerates battery wear

Pair this with the output calculator, savings calculator, and system cost calculator

The output calculator estimates per-state PV production, the savings calculator translates that into bill offset, and the cost calculator gives you the up-front capital. Combine all three to size a solar + EV system that covers both household and transportation electricity.

Sources

Frequently asked questions

How long does it take to charge an EV from 20% to 80% on a Level 2 charger?
On a typical 11.5 kW (48 A / 240 V) Level 2 home charger, going from 20% to 80% on a 75 kWh battery (the size of a Tesla Model 3 Long Range, Hyundai Ioniq 5, or Ford Mustang Mach-E) takes about 4 hours 20 minutes. The calculator above factors in real-world AC charging losses of roughly 10% — so the wall draws ~50 kWh to put 45 kWh into the battery. A 7.7 kW (32 A) wallbox stretches the same charge to about 6.5 hours, while a 50 kW DC fast charger completes it in 50-55 minutes once the taper above 80% is accounted for.
How much does it cost to charge an EV at home in the United States?
At the 2026 U.S. residential average of $0.16/kWh (EIA), a 20-80% charge on a 75 kWh battery costs around $8 of grid electricity. Off-peak time-of-use rates in California, New York, and the Northeast can drop that to $4-5 per session, while peak summer rates in Texas and Arizona push it up to $10-12. Charging exclusively during a TOU 'super off-peak' window (midnight to 6 AM in PG&E EV2-A, for example) is the single biggest lever for cutting EV running costs.
Will my solar panels actually charge my EV?
Yes — but only the solar production that overlaps with the time the car is plugged in. A 6 kW rooftop array generates roughly 25 kWh on a clear summer day in the lower 48 (NREL PVWatts), enough to put 50%+ of a 75 kWh battery in directly. Most U.S. homeowners on net metering 2.0 or NEM 3.0 get the rest of the value as a kWh credit on the bill, so even charging at night you can hit 100% solar offset on an annual basis if your array is sized right. The Solar Output Calculator on this site has a per-state production estimate.
What's the real-world charging efficiency of a U.S. home Level 2 charger?
AC Level 2 charging is typically 88-92% efficient end-to-end. Losses come from the wall-to-battery rectifier (5-7%), thermal management (1-3%), and trickle losses while plugged in idle (less than 1%). The calculator defaults to 90%. DC fast charging is slightly higher at 92-95% (less rectification on board) but adds significant battery degradation over time, so most U.S. drivers reserve DC fast for road trips.
Is it cheaper to charge at home or use a public DC fast charger?
Home charging at $0.16/kWh costs about $0.04 per mile in a typical 4 mi/kWh EV. EVgo, Electrify America, and Tesla Supercharger DC fast rates run $0.36-$0.55/kWh in 2026, so highway DC fast charging costs $0.09-$0.14 per mile — roughly 2-3× home charging. Use the calculator to compare: enter your battery size and the relevant tariff for each scenario and the cost figure scales linearly. Most U.S. EV owners do 85-90% of charging at home and reserve fast charging for trips over 200 miles.

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