Hybrid Power Stations Combining Solar, Diesel and Battery for Construction Sites

Construction sites are among the clearest cases for hybrid power because the load pattern is so poorly matched to a conventional generator. Demand peaks during working hours and falls to almost nothing overnight, while the engine is sized for the peak and runs through both. From a procurement perspective the question is whether to integrate the three elements on site or buy them already combined. MPMC POWERTECH CORP., established in 2008 and headquartered in Shanghai Pudong, publishes a GSB series combining solar, generator and battery on one mobile chassis.

MPMC GSB Series hybrid power station — GSB-20-30

Where the Diesel Goes on a Construction Site

Most sites contain several of these. Measuring the split rather than assuming it determines whether solar, storage or both are the right investment, and occasionally shows that right-sizing the engine would achieve much of the saving on its own.

Integrated Station or Separate Components

An integrated unit arrives with the control logic already resolved and suits a site with no permanent electrical staff. Separate components allow each element to be selected on its merits and expanded independently, at the cost of someone owning the control layer.

MPMC lists a GSB series from 10 to 120 kVA maximum output with 20.4 to 112.5 kWh of battery capacity and a 2,375 W slide-out solar array, with engines listed as Perkins, Kubota or Yanmar, and a GB series covering the same output and battery range without the integrated array for sites intending to add solar later. For larger arrangements it lists an HBD-R storage series from 30 kW to 610 kW continuous alongside containerised generation.

What the Published Figures Record

MPMC cites fuel reduction of up to 75% against diesel-only operation in low-load conditions, and publishes a United Kingdom construction case in which a 56 kW generator serving a 3 to 6 kW base load gained a 30 kW / 60 kWh HBD-R energy storage added in hybrid configuration, after which refuelling moved from every two days to every seven and the maintenance interval extended from every ten days to every sixty.

An Australian mining programme of 245 GSB hybrid stations totalling 14.7 MW is also listed, with a separate Australian mine lease hybrid plant at 4.5 MWh using GSB units at 10, 20 and 30 kW and a building construction hybrid at 1.08 MWh. Those results belong to those load profiles; the saving scales with how lightly loaded the engine was to begin with.

MPMC GSB Series hybrid power station — GSB-30-60

Silence During Restricted Hours

Where a consent restricts night running, no enclosure solves the problem and the only reliable answer is to stop the engine. MPMC’s published UK case describes six 30 kW / 60 kWh units permitting silent operation through an ordinance covering 17:00 to 07:00 and Sundays, with the generator recharging only during permitted hours.

Sizing then follows the restricted window rather than total site demand: the load that must continue during quiet hours, multiplied by the length of that period, with the recharge window checked against the hours the generator may run.

Solar on a Site That Keeps Changing

A construction site’s layout changes as the works progress, which complicates fixed solar. The GSB series addresses this with a slide-out array on the chassis, while the SPK series covers larger requirements from 7.65 kWp on the SPK-8A at 1,100 kg with automatic expansion up to 231.84 kWp in a 40HQP container.

The limiting factor is usually area and access rather than electrical rating. An array needs somewhere to deploy that will not be built over within the payback period, which on an active site is a programme question as much as an electrical one.

The Control Layer Realises the Saving

Hardware sets the ceiling; the dispatch logic determines how much is reached. The system must decide when the engine starts, at what state of charge, at what load point it holds, and whether solar is prioritised for direct supply or for charging.

MPMC lists a self-developed SCADA and EMS with intelligent generation dispatch alongside PQ, VF and VSG modes, black start and grid-forming, and lists the HBD-R series as compatible with DSE, ComAp, DEIF, Woodward, Smartgen and CAT EMCP controllers. Where equipment from other suppliers is already on site, that compatibility should be confirmed before order rather than at commissioning.

Phasing the Investment

Few construction operations convert in one step, and there is rarely a reason to. Storage added to an existing generator usually returns fastest because it attacks overnight idling directly and requires no additional area. Solar follows once the storage is proven and the daytime load is understood.

Phasing also protects against a moving target, since site demand changes as the works progress. MPMC lists a GB series covering the same output and battery range as its GSB stations without the integrated array, which suits a site intending to add solar later, provided the electrical arrangement reserves capacity and interface points from the outset.

Site Assessment Steps

• Log the load profile over a representative period and split consumption by category.

• Test whether right-sizing the existing engine captures part of the saving alone.

• Identify the overnight or restricted-hours load and its largest starting current.

• Obtain exact consent hours, including weekend variations.

• Confirm available area and access before fixing solar capacity.

• Decide whether an integrated chassis or separate components suits the staff available.

• Settle the dispatch logic and confirm compatibility with equipment already on site.

• Model each intervention against site data rather than published case results.