Levelise has launched the Levelise Calculator, a free, open-source tool designed to help installers, energy managers, and system designers accurately model the financial performance of battery storage systems.
Now live, the Levelise Calculator simulates system performance across a full year at half-hourly granularity, enabling professionals to move beyond high-level assumptions.
Unlike conventional calculators, the tool incorporates real UK market revenue mechanisms, allowing users to assess how value stacks up across multiple income streams, including Capacity Market participation, flexibility and response services, and smart tariff arbitrage.
The calculator is built to work with real operational data. Users can paste consumption and generation profiles directly from spreadsheets, making it suitable for validating proposals, stress-testing assumptions, and comparing design options using site-specific inputs.
A key differentiator is transparency. The Levelise Calculator is delivered as a single HTML file with no server dependencies. All calculations are visible in the source code, and no user data is transmitted or stored.
Iván Castro, Managing Director at Levelise, said, “Customers deserve to understand exactly how energy savings are calculated. That means no black boxes, no opaque assumptions, and no ‘trust us’ estimates. By making the code fully open and auditable, we enable installers and energy managers to verify the maths, challenge assumptions, and build confidence in their proposals.”
The same methodology applies across use cases, from residential battery evaluations and housing developments to commercial and industrial energy strategy.
The Levelise Calculator is available now at labs.levelise.com.
