Home›Energy Consumption›Solar EV Truck Calculator

Solar EV Truck Calculator

Enter fleet size, vehicle class, and daily miles — get solar kW needed, charger infrastructure cost, and annual fuel savings vs. diesel for Class 8 semis, box trucks, and delivery vans.

Fleet details
vehicles
mi/day
Financial inputs
$/kWh
$/gal
Solar EV fleet charging system
109 kW solar for 1 vehicle
Daily kWh per vehicle600.0 kWh/day
Total fleet daily kWh600.0 kWh/day
Solar system size108.6 kW
Battery buffer storage198.0 kWh
Chargers needed1 charger ($85,000)
Total system cost$359,680
ITC + MACRS savings-$109,872
Net cost after incentives$249,808
Annual electricity cost$26,280/yr
Annual diesel cost (equivalent)$67,385/yr
Annual fuel + maintenance savings$50,960/yr
Solar payback period4.9 yrs
Link copied to clipboard

How to Use This Calculator

Select your vehicle type and fleet size

Choose the vehicle class that matches your fleet. Class 8 semis like the Tesla Semi carry a 600 kWh battery and consume about 2 kWh per mile — the most energy-intensive vehicles. Delivery vans (Rivian EDV, eSprinter) are much more efficient at 0.38 kWh/mile with 90 kWh batteries. Enter the exact number of vehicles that will charge at this depot.

Enter daily miles and charger type

Daily mileage per vehicle is the key energy input. Multiply this by the vehicle's kWh/mile efficiency to get daily charging demand per vehicle. Charger type determines infrastructure cost and charging speed. For overnight fleet charging, L2 (19.2 kW) is cost-effective. For vehicles needing back-to-back runs, DCFC 150–350 kW chargers are required.

Set electricity rate and diesel price for TCO comparison

The calculator compares annual electricity cost for EV charging against the diesel fuel cost for equivalent mileage. Large commercial depots often qualify for demand charge management and time-of-use rates as low as $0.06–0.09/kWh — significantly lower than the commercial average. Enter the diesel price to get an accurate total cost of ownership comparison.

The Formula

Daily kWh per Vehicle = Daily Miles × kWh/mile efficiency Total Daily Fleet kWh = Daily kWh per Vehicle × Vehicle Count Solar kW = Total Daily kWh ÷ Peak Sun Hours ÷ 0.85 efficiency Battery Buffer = Total Daily kWh × 0.33 (8-hr overnight buffer) Total Cost = Solar + Battery + Charger Infrastructure Net Cost = Total Cost − (30% ITC + 10% MACRS) on solar + battery Annual Diesel Cost = (Miles × 365 × Vehicles) ÷ MPG × $/gallon Annual Savings = (Diesel Cost − Electric Cost) + Maintenance Savings Payback = Net Cost ÷ Annual Savings

The maintenance savings use industry estimates of $0.15/mile for diesel heavy vehicles vs. $0.06/mile for electric equivalents — a $0.09/mile difference covering oil changes, DEF fluid, transmission service, and brake replacement (regenerative braking significantly extends brake life). Over a 300-mile/day Class 8 truck, this is $9,855/year per vehicle in maintenance savings alone.

Example

Last-mile logistics — 20 Rivian delivery vans, Los Angeles

A parcel delivery company has 20 Rivian EDV700 vans at an LA depot. Each runs 80 miles/day. They have a large depot roof and want to offset charging costs with solar, using L2 chargers for overnight charging at $0.13/kWh commercial rate.

Fleet20 delivery vans (90 kWh)
Daily miles80 mi/day per van
LocationLos Angeles, CA (5.6 PSH)
Electricity rate$0.13/kWh
Diesel equivalent$3.80/gallon, 16 MPG

Result

Daily fleet energy608 kWh/day (20 × 30.4 kWh)
Solar system~128 kW
Battery buffer~200 kWh
Annual fuel savings~$144,000/yr vs diesel
Maintenance savings~$52,560/yr
Net system cost (after ITC)~$195,000
Payback~1.0 yr on combined savings

A 20-van electric fleet in LA saves nearly $200,000/year combined in fuel and maintenance. The solar system pays back in about 1 year on those savings alone — and adds energy independence, protection from utility rate increases, and strong ESG credentials for corporate reporting. The 128 kW rooftop array fits on a typical 15,000 sq ft warehouse roof.

FAQ

A Tesla Semi traveling 300 miles/day consumes approximately 600 kWh/day (2 kWh/mile). In Phoenix (6.5 PSH), offsetting this with solar requires about 115 kW of solar panels — roughly 260 × 440W panels, covering about 14,000 sq ft. In less sunny areas like Chicago (4.4 PSH), the same truck needs 170 kW. Most fleet depots don't have enough roof space for full solar offset of Class 8 trucks; grid supplementation is typical. A Tesla Semi depot with 10 trucks needs 1.1–1.7 MW of solar — essentially a small solar farm.
Class 8 electric trucks require high-power DCFC chargers. The Tesla Semi uses the Tesla Megacharger (1 MW capable, 350 kW deployed), which can add 400 miles in 30 minutes. Volvo VNR Electric and Freightliner eCascadia use CCS DC chargers at 150–250 kW. For overnight depot charging (8–10 hours), a 50–150 kW charger is sufficient and dramatically cheaper to install ($15,000–35,000 vs. $85,000+ for 350 kW). For operations requiring back-to-back runs with minimal downtime, 350 kW chargers are necessary.
At typical commercial rates, electric freight is 60–75% cheaper per mile in fuel costs. A diesel Class 8 truck at 6.5 MPG and $4.00/gallon diesel costs $0.615/mile in fuel. A Tesla Semi at 2 kWh/mile and $0.10/kWh electricity costs $0.20/mile — saving $0.415/mile. Over 300 miles/day and 300 operational days, that's $37,350/year per truck in fuel savings. Add $9,855/year in maintenance savings ($0.09/mile advantage), and a single truck saves ~$47,000/year vs. diesel — a powerful economic case independent of solar.
Solar can meaningfully offset fleet charging costs but rarely covers 100% of a large truck fleet's needs. Practical constraints: (1) Roof area — a 10-truck Class 8 depot needs ~1 MW of solar, requiring ~115,000 sq ft (2.6 acres) of panel coverage. Most depots don't have that roof area. (2) Peak demand charges — solar reduces energy charges but not always peak demand charges. (3) Solutions: solar canopies over parking areas, ground-mount in adjacent land, and pairing with on-site battery storage to shave demand peaks. A hybrid 200–500 kW solar + 500 kWh battery system is practical for most depots and significantly reduces charging costs.

Related Calculators

🚀 Solar Drone Charging Station
Size solar for remote drone fleet charging operations.
🚌 EV Solar Calculator
Solar panels to charge a passenger electric vehicle at home.
💰 Solar Tax Credit Calculator
Calculate ITC and MACRS depreciation for commercial solar.
📈 Solar Savings Calculator
Annual bill savings and payback for any solar installation.

Embed This Calculator

Free to embed on your website. Just copy this code:

<iframe src="https://solarsizecalculator.com/solar-ev-truck-calculator"
  width="100%" height="750" frameborder="0"
  title="Solar EV Truck Calculator"></iframe>