Buyer guide
What to include in a BESS quote
A good quote starts with a good brief. This guide covers what to send, and what you should expect to see written down in return.
How to use this guide
Part 1 is what you send. Part 2 is what a quote should state back. Gather what you have and mark the rest “not sure”. Unknowns are normal at the start; a supplier should be able to work with them and tell you which ones matter.
Part 1: what to send
The project
- Country and site location
- What needs power: crane, hoist, site supply, cabins, plant
- The problem to solve: fuel cost, generator runtime, limited grid, quiet hours, emissions
- Required start date and expected duration
- Hire, purchase, or open to advice
The loads
- Largest load in kW or kVA, and what causes it
- Current generator rating in kVA, if there is one
- Average load, if it has been measured
- Equipment list with motor ratings and starting method
- Working hours and the busiest periods
- Any hours a generator must not run
Supply and charging
- Supply on site today: grid, generator, both or neither
- Grid connection capacity, and how much is spare
- Generator make, model and controller
- Site voltage, phase and frequency
- Recorded fuel use, if available
Site and access
- Expected temperature range; coastal, dusty or corrosive conditions
- Vehicle access and ground conditions at the set-down point
- Lifting equipment available on site
- Space available for the unit and working clearance
- Who is responsible for distribution and connection
Part 2: what the quote should state back
Equipment and configuration
- Manufacturer, model and regional variant
- The data sheet revision and date the figures come from
- Optional features included, listed separately from the standard specification
- Confirmation that the variant suits your site voltage and frequency
Output
- Nominal output in kW and kVA
- Each overload rating with its duration
- Any conditions on repeated overloads
- Derating at your expected site temperature
For reference, the Ampd 400 brochure gives a nominal output of 386 kW / 428 kVA, with overload ratings of 466 kW / 496 kVA for up to 60 seconds and 585 kW / 595 kVA for up to 10 seconds. A quote should present its figures the same way: sustained rating first, time-limited ratings with their limits.
Energy
- Nominal DC capacity in kWh
- Usable AC energy for the configuration, and the assumptions behind it
- Expected runtime on your duty, stated as an estimate with its basis
- Any reserve held back
Charging
- Charging source assumed: grid, generator or both
- Charging power assumed to be available on your site
- The energy balance across a working day
- Generator control compatibility, and who verifies it
Delivery and installation
- Delivery, offloading and lifting: who provides what
- Weight and dimensions of the configuration quoted
- Cables, connectors and distribution equipment included
- Collection at the end of a hire
Commissioning and support
- Who commissions the system and signs off the configuration
- Monitoring and connectivity, and any ongoing charges
- Who to call for a fault, and the service arrangement in your territory
- What happens if a unit fails during the project
Warranty and documents
- Warranty duration and the full terms
- Any warranted capacity or throughput
- Exclusions, and whether labour and travel are covered
- Certification documents for the exact model and configuration, with their scope
Read certification entries closely. A cell-level test listing is not a system-level certification, and some standards apply only to units fitted with a particular option. Ask for the document, not the badge.
Commercial terms
- Who you are contracting with, and who invoices
- Price broken down: equipment, delivery, commissioning, accessories, software
- Hire period, extension and early-return terms; or purchase and payment terms
- Exclusions and assumptions
- How long the quote is valid
Questions worth asking
- Which figure in this quote is sustained, and which is time-limited?
- Is the energy figure nominal or usable?
- What load profile is the runtime estimate based on?
- What would change the price or the configuration after a site survey?
- What is not included?
Start your brief
Our project brief builder asks for the Part 1 information step by step, accepts “not sure”, and gives you a summary to keep before you enter any contact details. Maximum Energy Solutions arranges technical assessment and fulfilment through specialist supply partners; the proposed equipment, costs and contracting party are confirmed in your proposal. Get a site power proposal.
Source: Ampd 200 IEC brochure, Rev 1.3, dated 29 April 2026; Ampd 400 IEC brochure, Rev 1.3, dated 29 April 2026. Manufacturer-published figures for the IEC variant, not independently tested. Specifications can change, so the current data sheet for your territory is confirmed in a project proposal.
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.
Questions buyers ask
What information does a supplier need to quote for a site battery?
At minimum: the country and site location, what needs power, the problem you want to solve, the supply on site today, the start date and duration, whether you want to hire or buy, and the largest load or current generator size. Technical details such as voltage, charging capacity and access shorten the review but are not needed to start.
What should a battery storage quote state about output?
The nominal output in kW and kVA, and any overload ratings with the duration each applies for. A maximum output figure without a time limit is incomplete. The quote should also identify the exact model, variant and document revision the figures come from.
Should a quote give usable energy or nominal capacity?
Both, clearly labelled. Nominal DC capacity is the rating at the battery. Usable AC energy is what reaches your loads and is the figure that determines runtime. If only nominal capacity is given, ask for usable energy and the assumptions behind it.
Is cell cycle life the same as a warranty?
No. A rated cell cycle life describes the battery cells under test conditions. A warranty is a separate commitment with its own duration, terms and exclusions. Ask for the full warranty terms, including any warranted capacity or throughput.