Buy or hire a site battery

Start with utilisation

A site battery is capital equipment. Like a crane or a generator, it pays for itself only while it is working.

So the first question is not the price. It is: how many weeks of the year would this unit be on a suitable job?

• One project, a few months long: hire.
• A run of similar projects, with gaps between them: compare carefully.
• A steady pipeline that keeps the unit working most of the year: purchase becomes worth pricing.

“Suitable” matters. A unit sized for tower cranes is not automatically right for the next job’s cabins and lighting. Count only the projects it genuinely fits.

What hiring gives you

• No capital outlay. Cost follows the project.
• The right unit for each job. Each project can have a different size or arrangement.
• Service is someone else’s responsibility. Maintenance and faults sit with the provider, on the terms of the hire.
• A way to learn. A first hire shows how the application behaves before any longer commitment.

The trade-off is a higher cost per week than ownership at high utilisation, and dependence on availability when you need it.

What buying brings with it

Ownership can lower the cost per working week. It also makes you responsible for things a hire company would handle.

Responsibility	What it means in practice
Transport and lifting	Moving a unit of several tonnes between sites, each time
Storage	Secure space, and care of the battery, between projects
Commissioning	Set-up and connection at each new site
Service and support	Who maintains it, and how quickly faults are attended
Warranty conditions	What is covered, for how long, and on what conditions
Software and connectivity	Any ongoing charges for monitoring or updates
Ageing	Battery capacity reduces with use and time
Resale value	What the unit is worth when you no longer need it

The reference units are substantial: maximum wet weight is 5,500 kg for the Ampd 200 and 9,000 kg for the Ampd 400. Moving and storing them is a real cost line.

Reading the life and warranty figures

Two figures in the manufacturer’s brochures are easy to over-read.

Rated cell life. The brochures list 9,000 cycles as the rated life of the battery cells, where a cycle is one full charge and full discharge. They state that this does not equal warranted cycles. It is a cell rating, not a promise about the system’s life or its capacity at any point.

Warranty duration. The brochures list a five-year warranty. They do not state what it covers, whether it carries capacity or throughput conditions, or what it excludes.

If you are considering a purchase, ask for the full warranty terms, the service arrangement in your country and any ongoing charges before comparing prices. The guide to what to include in a BESS quote lists the questions.

A simple way to compare

Work out two figures for the same period, say three years.

Hire cost = weeks you expect to need a battery × weekly hire rate, plus delivery and set-up for each project.

Ownership cost = purchase price and financing, plus transport, storage, service and software for the period, less the value you expect to recover at the end.

Then test the answer against utilisation. Halve the number of working weeks and see whether ownership still wins. If the case only works at full utilisation, it is a fragile case.

We do not publish hire rates or purchase prices, because both depend on the equipment, the territory and the supply route. A proposal provides them.

A staged approach

Many buyers do not need to decide at the start.

1. Hire for the first project. Confirm the application works on a real site, with real loads.
2. Measure. Record fuel, running hours and any problems. This is the evidence for the next decision.
3. Review the pipeline. If more suitable projects are coming, price a purchase against continued hire.

What we confirm for each project

We are a distributor working with specialist supply partners. For each enquiry, the proposal states:

• whether hire, purchase or both are available for that project and location;
• the equipment, configuration and options;
• the costs, and what is and is not included;
• who you would contract with, and who provides service and warranty support.

Tell us your preference in the site power assessment. “Open to advice” is a valid answer.

Product figures on this page: Ampd 200 Brochure IEC Rev 1.3, dated 29 April 2026; Ampd 400 Brochure IEC Rev 1.3, dated 29 April 2026. Manufacturer-published, not independently tested.