Emissions-free energy system saves heat from the summer sun for winter

A catalyst for controlling the release of the stored energy.

The energy system MOST works in a circular manner. First, the liquid captures energy from sunlight, in a solar thermal collector on the roof of a building. Then it is stored at room temperature, leading to minimal energy losses. When the energy is needed, it can be drawn through the catalyst so that the liquid heats up. It is envisioned that this warmth can then be utilised in, for example, domestic heating systems, after which the liquid can be sent back up to the roof to collect more energy -- all completely free of emissions, and without damaging the molecules. Credit: Yen Strandqvist/Chalmers University of Technology
The energy system MOST works in a circular manner. First, the liquid captures energy from sunlight, in a solar thermal collector on the roof of a building. Then it is stored at room temperature, leading to minimal energy losses. When the energy is needed, it can be drawn through the catalyst so that the liquid heats up. It is envisioned that this warmth can then be utilised in, for example, domestic heating systems, after which the liquid can be sent back up to the roof to collect more energy -- all completely free of emissions, and without damaging the molecules. Credit: Yen Strandqvist/Chalmers University of Technology

Scientists at the Chalmers University of Technology, Sweden have designed molecule which can store solar energy for later use. Scientists have built up a catalyst for controlling the release of the stored energy. The impetus goes about as a filter, through which the liquid streams, making a reaction that warms the fluid by 63 degrees Celsius.

In the event that the fluid has a temperature of 20 degrees C when pumped through the filter, it turns out the opposite side at 83 degrees C. In the meantime, it restores the particle to its unique frame, so it very well may be then reused in the warming system.

Its been almost a year, scientists presented a molecule that was capable of storing solar energy. The molecule, made from carbon, hydrogen, and nitrogen, has the unique property that when it is hit by sunlight, it is transformed into an energy-rich isomer—a molecule consisting of the same atoms, but bound together in a different way.

This isomer can then be stored for use when that vitality is later required—for instance, during the evening or in winter. It is in a liquid form and is adjusted for use in a solar energy system, which the specialists call the Molecular Solar Thermal Energy Storage (MOST) framework. In the most recent year, the specialists have made awesome advances in the improvement of MOST.

Kasper Moth-Poulsen, a professor at the Department of Chemistry and Chemical Engineering said, “The energy in this isomer can now be stored for up to 18 years. And when we extract the energy and use it, we get a warmth increase greater than we dared hope for,” says the leader of the research team.”

Along with this, scientists learned to improve the design of the molecule to increase its storage abilities so that the isomer can store energy for up to 18 years. This was a critical change, as the focal point of the undertaking is fundamentally chemical energy storage. Besides, the framework was beforehand dependent on the utilization of the combustible chemical toluene. However, now, the specialists have figured out how to evacuate the possibly dangerous toluene and rather utilize just the energy-storing molecule.

These advances mean that the MOST system now works in a circular manner. First, the liquid captures energy from sunlight, in a solar thermal collector on the roof of a building. Then it is stored at room temperature, leading to minimizing energy loss.

When the energy is needed, it can be drawn through the catalyst so that the liquid heats up. It is envisioned that this warmth can then be utilized in domestic heating systems, after which the liquid can be sent back up to the roof to collect more energy—all completely free of emissions, and without damaging the molecule.

Kasper Moth-Poulsen said, “We have made many crucial advances recently, and today, we have an emissions-free energy system that works all year around.”

The solar thermal collector is a concave reflector with a pipe in the center. It tracks the sun’s path across the sky and works in the same way as a satellite dish, focusing the sun’s rays at the point where the liquid leads through the pipe. It is even possible to add on an additional pipe with normal water to combine the system with conventional water heating.

Kasper Moth-Poulsen said, “There is a lot left to do. We have just got the system to work. Now we need to ensure everything is optimally designed.”

These advances have been presented in four scientific articles, the most recent appearing in Energy & Environmental Science.