German scientists tried to determine if a PV system linked to a small electrolyser, a fuel cell and lithium-ion batteries could fully power a grid-connected household. Their new proposal consists of a 6.8 kW photovoltaic generator, a 5 kW electrolyser, a 1.24 kW fuel cell system and a storage battery.
Researchers from the University of Paderborn in Germany have developed a model for deploying residential photovoltaic panels on rooftops in combination with batteries for short-term storage and hydrogen for long-term storage.
“The design of the system was inspired by a residential building, but it can also be used for other buildings if the load curves for electricity and heating are known,” said researcher Stefan Krauter. photo magazine.”It can give autonomy to electricity all year round.
the the decentralized energy system is designed to cover the main electricity demand of a household via photovoltaics, even in winter, including sufficient storage capacity.
“The goal is to minimize the grid load by achieving low or even zero interaction with the grid, which is achieved through the use of decentralized long-term energy storage,” the scientists explained.
The system uses a 6.8 kW photovoltaic generator and a 5 kW generator electrolyser powered by excess solar energy to produce hydrogen, which is then stored in a hydrogen tank via a compressor. In times of high energy demand, when photovoltaic production is not sufficient, the green fuel is used to generate electricity via a 1.24 kW fuel cell system. Lithium-ion batteries are part of the proposed system configuration to react to too rapid load changes, which the hydrogen system would not be able to handle.
the the waste heat generated by the fuel cell and the electrolyser is transferred via heat exchangers to a hot water tank, which supplies hot water to the household. The remaining demand is covered by a heat pump.
Academics have tried to identify the the type and size of components required in different scenarios. They also aimed to assess the conditions under which a system could compete with conventional electrical systems in terms of price and cost. The model was simulated in Simulink (MATLAB) to analyze when and how the PV system is fully capable of covering the energy needs of a household.
The scientists also used HOMER software, developed by the US National Renewable Energy Laboratory (NREL), to verify the results. The measurements were taken with a temporal resolution of 15 minutes and a total time one year framework.
The German group estimated that the electrolyser used 4283.55kWh of excess solar electricity to be produced 80.50 kg of hydrogen in a year, while the fuel cell was able to return 1009.86 kWh of energy by burning 73.52 kg of hydrogen.
” The compressionn of hydrogen required an annual energy demand of 268.14kWh, while the heating demand was 1208.66kWh“, explained the scientists. “The heating ofdemand has been reduced by 643.69kWh by wethe waste heat product in the electrolyser and the Fuel cell.”
They said their simulation via Simulink showed as the demand for home heating increases the amount required of decentralized stored hydrogen when aiming for energy independent operations.
“Future research needs to focus on optimizing the control system and analyzing component sizing under which scenarios are preferable in terms of energy and resource efficiency and in terms of increased life. of life,” they said.
The scientists described the system design in “Hybrid energy system model in Matlab/Simulink based on solar energy, lithium-ion battery and hydrogenwhich was recently published in Energies.
This content is copyrighted and may not be reused. If you wish to cooperate with us and wish to reuse some of our content, please contact: [email protected]