The Sol-ion trials will see Li-ion (lithium-ion) batteries used in PV systems. The trials will be used to assess the performance of the technology, its economic viability, the added value of energy storage in an on-grid system and the benefits to stakeholders.
Currently, the majority of grid-connected PV systems do not include energy storage and the electricity produced is fed into the grid directly. The concept of the Sol-ion energy conversion and storage project is that solar energy can be ‘time-shifted’ to periods of peak demand or when there is no sun, allowing self-consumption or grid support.
According to the companies, this will reduce the impact of intermittent injection to power grids, thus allowing a high penetration of PV energy in the electricity mix.
The Sol-ion kit has been developed to accommodate PV energy production of 5kWp (peak) with a battery rated from 5 to 15kWh and a voltage of 170V to 350V. Li-ion technology also meets the project’s need for 20-year battery life.
The Sol-ion battery is based on Saft’s Li-ion modules, with a voltage of 48V and 2.2kWh capacity. These modules can be connected in series or parallel to create the required voltage and capacity for each installation.
The energy conversion and system management systems are designed to handle four system functions: multidirectional energy flows; self-consumption; grid support; back-up.
They are also intended to handle requirements for demand side management such as control over storage and loads using smart metering, and integration within future smart grids that will need to handle demand response.
