Why CIGS solar cells on buses make sense
A modern diesel bus uses far more fuel than most people realise. Propulsion is only one part of the equation. The other part is power - 24V power for all the equipment that runs around the clock: lighting, ventilation, air conditioning, door systems, information screens, cameras and electronics. The engine's generator provides all that power. And the generator draws diesel.
This is where flexible CIGS solar cells on buses make a measurable difference.
The hidden diesel cost - power from engine
When the bus is running at normal speeds, the generator consumes approximately 1 litre of diesel per kWh. If the bus is idling, the figure rises to 4-8 litres per kWh. Idling is the most expensive way to generate power - and for coaches parked for hours on end, this scenario repeats itself day after day.
Idling is the most expensive and inefficient way to generate power - but it's often necessary to keep equipment running. This is where the big savings potential arises.
660 Wp CIGS - up to 1,000 litres of diesel saved per year
SunPower2u's complete 660 Wp CIGS solar cell kit is mounted directly on the roof of the bus and produces power to relieve the generator. Under normal operating conditions, the system saves up to 1,000 litres of diesel per year.
Savings depend on driving patterns, geographical location and total electrical load. In Southern Europe, the potential is highest. In Northern Europe it is lower - but sufficient to keep the payback time short.
For long-distance coaches, the primary benefit is not fuel. It's in the vehicle batteries.
Double battery life - an underestimated benefit
Batteries left uncharged for days or weeks will sulphate. This shortens the lifespan and increases the risk of starting problems. CIGS solar cells on the roof keeps the batteries in constant balance - even during standstill.
This typically means double the battery life, fewer emergency recharges and safe starting even after long breaks. For bus operators with larger fleets, this represents an operational benefit that over time exceeds fuel savings and promotes the use of green energy.
Contact Jens Ottosen to learn more about CIGS solar cells on buses.
Why CIGS is the right technology for buses
CIGS - Copper Indium Gallium Selenide - is a thin-film technology that differs from conventional silicon panels in precisely those points that count in mobile applications.
The panels are lightweight and do not put unnecessary strain on the vehicle. They are flexible and follow the roof profile of the bus without frames that increase air resistance. They produce power in partial shade, at high temperatures and in dim winter light - conditions that significantly reduce the yield of rigid crystalline panels.
They can also withstand vibrations. This is not a given. Traditional glass-based panels crack over time under the shocks and jolts of driving. CIGS panels are built for movement.
That's why CIGS solar panels are increasingly being used as Solar solution for all segments of the transport industry - from scheduled buses and coaches to specialised vehicles and refrigerated trucks.
Smart energy management with Victron
SunPower2u combines CIGS technology with Victron energy management that continuously optimises MPPT charging and makes full use of the power produced. The system delivers stable battery charging and proven reliability - standardised for bus applications with 660 Wp, exceeding the majority of competing CIGS solutions on the market.
Economics - what does it cost and when will it pay for itself
A complete 660 Wp solar PV system costs €2,365 excluding installation. Installation takes 3-4 hours and requires basic electrical expertise.
With annual savings of up to 1,000 litres of diesel, the payback time is short. Exactly how short depends on the diesel price and operating profile - but the maths is straightforward.
In addition, reduced CO₂ emissions, lower engine load, fewer service intervals and a strengthened sustainability profile - factors that are increasingly important in tenders and public contracts.
CIGS solar cells on buses - an investment in operation
We are the experts in the field. CIGS solar cells on buses is our field and we have many years of experience developing and implementing solar solutions for the transport sector.
A CIGS solar kit from SunPower2u doesn't solve one problem. It solves three: it lowers fuel consumption, it extends battery life and it reduces the mechanical load on the generator.
Our solar system is manufactured in Europe and proven for mobile applications. For bus operators running fleets with high operating costs, it's an investment with a direct and predictable return.
