The H2TOP concept aims to address the current complexity and inefficiency in producing hydrogen from renewable energy sources, by replacing the conventional power electronics with a robust, low-cost and high energy efficiency novel architecture.

Producing hydrogen by electrolysis has traditionally required multiple stages of electric power conversion before electrical power is delivered to the electrolyser stack (a set of all electrolytic cells). This results in significant efficiency losses, with the largest occurring during the DC-AC and AC-DC conversions. The renewable energy sources and the hydrogen production plants are often separated by long distances resulting in the use of the electrical grid to deliver power to the plant. Excluding the electric Transport and Delivery (T&D) losses, the net efficiency loss between the PV power plants and the electrolysers amounts to approximately 10%, with higher losses when the PV plant is operated at a low solar irradiation level.

Hydrogen Waves addresses these problems by introducing the H2Top architecture, which eliminates both the solar PV inverter and the electrolyser Power Supply, along with their associated losses. With these radical changes, H2Top reduces the energy transmission losses to less than 1%, while simultaneously reducing plant cost and increasing its reliability. Green hydrogen is forecasted to form a large part of the energy mix within the UK Net Zero agenda. This project is an enabler to produce the fuel locally in the UK at a lower cost and higher efficiency than is currently possible. The cost of green hydrogen in Wales is forecast to be £4.13/kg at year 2030 when produced from PV. According to IRENA data and our own internal cost model, introducing the H2Top architecture could save up to 18.5%.