Developed by U.S. scientists, the Hydrogen Energy Storage Evaluation Tool (HESET) can assess the economic and technical characteristics of individual system components and the modelling of each hydrogen pathway. Furthermore, it can help understand how hydrogen storage can be used for various grid and end-user services.

Researchers from Hong Kong have applied a novel charge-reinforced, ion-selective (CRIS) membrane to a polysulfide-iodide redox flow battery they had built in 2016. The redox flow battery showed a capacity decay rate of just 0.005% per day for 1,200 cycles, and a lifetime with over 2,000 hours’ cycling, which the academics said corresponds to approximately three months.

Underwater gravity energy storage has been proposed as an ideal solution for weekly energy storage, by an international group of scientists. The novel technology is considered an alternative to pumped-hydro storage for coasts and islands without mountains that are located close to deep waters, and may also be interesting for PV if used to store green hydrogen.

Conventional incentives such as renewable portfolio standards, feed-in tariffs or feed-in premium payments may lead to a price cannibalisation scenario for wind and solar, according to a new study from a German-Swedish research group. CO2 pricing is, however, considered an efficient tool to maintain their market value high enough to ensure new investments. A total system cost approach, rather than an LCOE perspective, is needed to understand the strong dependence of market value on policy choice though.

Researchers in China have built a PV-powered air conditioner that can store power through ice thermal storage. The performance of the system was evaluated considering operating efficiency and stability and the scientists found that a device relying on a variable-speed compressor and an MPPT controller showed very good ice-making capability.

In a white paper, the three Chinese module manufacturers have reiterated the well-known refrain “bigger is not always better.” Experts from the three companies compared the BoS costs of 182mm-wafer-based modules and 210mm products, and found that the former have a slight advantage in racking, foundation, and land costs.

Saudi scientists built the cell’s electrode with a hole-transporting molecule called Br-2PACz and not with the commonly used PEDOT:PSS. It helped improve the photovoltaic cell efficiency by around 0.9%.

An international research team has designed a residential solar-plus-storage system based on gravity. The system was built with a solar power generator, a bulk booster charge controller, an inverter, a solenoid device, a deep cycle battery, a pulley block, a geared motor, a microcontroller, and wire ropes. Its creators said the system is ideal for regions with high solar radiation. They found that, due to its high electrical requirements, the system needs to rely on high-power solar modules with an output of over 500 W.

US expert in environmental and energy policy Alexis Pascaris spoke with pv magazine about opportunities and barriers associated with agrivoltaics. Agrivoltaics are a very practical and advantageous alternative to large-scale solar, specifically in places where there are land-use constraints or needs for rural economic development, she explains. Differences in costs related to ground-mounted solar can typically be attributed to the raised racking systems or additional fencing, but these upfront investments in specialised hardware are eventually recovered as agrivoltaic systems produce dual-revenue streams.

According to a new study from LUT University, domestic water heating costs may be reduced by combining rooftop PV with geothermal heat pumps. Scientists developed a control method to minimise these costs by taking advantage of cheap spot market electricity and maximised PV power generation, as well as considering heat demand, PV generation forecasts, and heat pump efficiency.