Solar vs Diesel Site Vans: What It Really Costs to Run One
Most site vans still start the day the same way: someone fires up the generator, and it runs until knock-off. On a lot of sites it runs 24/7. Every hour it runs costs fuel, servicing and noise.
A Hardwear van flips that. The 48V Victron solar package and lithium batteries carry the load, and the 6 kVA generator is a back-up that only runs to top up the batteries when they need it.
The real-world data
We monitor our vans remotely through Victron VRM. Over August and September 2026 (61 days), one of our hire fleet vans, HW26012C, recorded:
- 96% of its power from solar
- 505.1 kWh generated by the solar panels
- Just 20.8 kWh from the generator, as a battery top-up on 8 of the 61 days
- Average use of about 8.5 kWh a day, or around 3,106 kWh a year
How the two setups compare
| Diesel generator running 24/7 | Hardwear solar-first van | |
|---|---|---|
| Primary power | 6 kVA diesel generator | 48V Victron solar: 6 x 440 W panels, 4 x 50 Ah lithium batteries |
| Generator role | Runs around the clock | Back-up only, charges the batteries |
| Generator use (61 days) | Every day, all day | Top-up on 8 days |
| Diesel per year | Up to 14,016 L | Top-up fuel only |
| Fuel and servicing per year | Up to $43,722 | Up to $43,722 a year saved |
| Refuelling | About every 16 hours (25 L tank) | Rarely |
| Noise | Around 61 dB(A) at 7 m, constantly | Quiet unless the back-up runs |
| Connectivity | Varies | Starlink enabled as standard |
What that means in dollars
Compared with a 6 kVA diesel generator running 24/7, a Hardwear van can save up to $119.79 a day. That adds up to:
- Up to $3,643 a month
- Up to $43,722 a year: $36,722 in fuel and $7,000 in generator servicing
- Up to $218,610 over five years
It also saves up to 38.4 litres of diesel a day, or 14,016 litres a year, and around 38 tonnes of CO2 a year.
What about winter and cloudy days?
The data above covers late winter and early spring, not a summer best case. Solar panels still generate from diffuse daylight, so the batteries keep charging on overcast days. When they need help, the back-up generator tops them up and switches off again.
The bottom line
A site van's purchase price is only part of its cost. Over a project, fuel, servicing, refuelling runs and downtime add up. A Hardwear van is built to bring all of them down, with the generator there when you need it and off when you don't.
See the HW7700 and HW9000 specifications or talk to the Hardwear team.
Savings are indicative. Based on Victron VRM data from Hardwear van HW26012C, 1 August to 30 September 2026 (61 days), annualised. The diesel comparison assumes a Denyo 6 kVA generator (DCA-6000SS) running 24/7 at 1.6 L/h (manufacturer figure at 75% load), diesel at $2.62/L (national average, 2 October 2026) and a $200 oil service every 250 hours. A generator at a van's lighter average load may use less fuel. Actual savings depend on site load, location, weather and fuel prices.
