BESS · Solární Panely.CZ
How to compare commercial battery storage proposals
Price per kWh is only a starting point. Compare usable energy, power, supply boundaries, service exclusions and the conditions behind promised benefits.
Align the duty before comparing the price
Two proposals with the same capacity may deliver different services. One may only shift surplus solar energy, while another includes backup, peak reduction or external dispatch. Define the required power, duration, operating window and critical loads first. Identify functions that are contractually committed and those only possible with additional equipment.
Request the distinction between nominal and usable energy and the conditions for available power. Temperature, SOC reserve, battery condition and the measurement boundary matter. DC power is not the same as power delivered at the site connection.
Compare the same supply boundary
- Battery modules, BMS, cabinets and thermal management.
- PCS or hybrid inverter, metering, switchgear and protection.
- EMS, licences, remote access and communications integration.
- Design, connection, site preparation, fire measures and inspections.
- Transport, handling, commissioning and agreed acceptance tests.
- Service, spare parts and costs after initial support expires.
A missing item cannot be assumed to cost zero. Ask whether it is included, excluded or dependent on a site survey. Highlight work and approvals that remain the investor’s responsibility. Without this boundary, a lower headline price may simply represent a smaller scope.
Require a model that explains the saving
Ask for baseline demand and generation profiles, time resolution, prices and dispatch rules. Separate gross benefit from charging costs, losses, auxiliary consumption, degradation and service. Revenue from an external service belongs in a separate scenario unless its commercial terms are secured.
Avoid double-counting capacity: energy reserved for backup cannot simultaneously be fully committed to another duty. The proposal must explain control priorities and their effect on the financial outcome. A brochure return-on-investment figure is not a substitute for site data.
Questions before signing
A warranty should define what is measured, under which conditions and who pays for diagnostics, transport, labour and replacement. Declared design life is not automatically a warranty for the same duration, capacity or savings. A local stock location is not a commitment to resolve a claim within a defined time.
Our review produces comparable scope items, risks, missing evidence and questions for suppliers. It is not a safety approval without inspection or a legal endorsement of a contract. The project determines which specialists are needed.
Sources and limits
Sources describe their own scope. A general document is not a project-specific certificate or evidence of our own physical test.
Advice before investment
Agree the assessment before choosing equipment.
This is a paid advisory service. Scope, fee, delivery date, named specialists and exclusions are agreed in a written proposal before work begins. Sending an enquiry is not an order or an obligation to purchase equipment.