Polysolar collaborate to create Low-impact Plant 2 Power Hub that generates renewable electricity from plants and the sun
Green wall technology and transparent solar panels have been combined to generate electrical current from a renewable source of energy both day and night, paving the way for simple and affordable power generation in developing countries.
A prototype “smart eco hub” that could eventually generate enough electricity to light itself, has been built by a collaboration of University of Cambridge researchers and eco-companies.
The ongoing living experiment, hosted by the Cambridge University Botanic Garden and open to the visiting public, is incorporated in a simple wooden hub, designed by architects MCMM. Eight vertical green wall units – created by green wall specialists, Scotscape – are housed along with four semi-transparent solar panels and two flexible solar panels by provided Polysolar.
The hub has specially adapted vertical green walls that harvest electrons the electrons naturally produced as a by-product of photosynthesis and metabolic activity, and convert them into electrical current. It is the brainchild of Professor Christopher Howe and Dr Paolo Bombelli, of the Department of Biochemistry. Their previous experiments resulted in a device able to power a radio using the current generated by moss.
The solar panels turn light into electricity by using mainly the blue and green radiation of the solar spectrum. Plants grow behind the , . The plants generate electrical currents as a consequence of photosynthesis and metabolic activity during the day and night.
“Ideally you can have the solar panels generating during the day, and the biological system at night. To address the world’s energy needs, we need a portfolio of many different technologies, and it’s even better if these technologies can operate in synergy,” said Bombelli.
The structure of the hub allows different combinations of the photovoltaic and biological systems to be tested. On the north east aspect of the hub, plants receive light directly, without being exposed to too much direct sun. On the south west orientation, a green wall panel is housed behind a semi-transparent solar panel so that the effect on the plants and their ability to generate current can be monitored. Next to that, in the same orientation, a single solar panel stands alone, and two further panels are also mounted on the roof.
“The combination of with renewable energy production constitutes a powerful solution to food and resource shortages on an increasingly planet,” explained Slota-Newsonfrom Polysolar. “We our semi-transparent solar panels into greenhouses, producing electrical energy from the sun which can in turn to power irrigation pumps or In this collaboration with Cambridge University, the public can experience the plants’ healthy growth behind Polysolar panels.”
The green wall panels in the hub are made from a synthetic material containing pockets, each holding a litre of soil and several plants. The pockets are fitted with a lining of carbon fibre on the back, which acts as an anode to receive electrons from the metabolism of plant and bacteria in the soil, and a carbon/catalyst plate on the front which acts as a cathode.
When a plant photosynthesises, energy from the sun is used to convert carbon dioxide into organic compounds that the plant needs to grow. Some of the compounds – such as carbohydrates, proteins and lipids – are leached into the soil where they are broken down by bacteria, which in turn release by-products, including electrons, as part of the process.
Electrons have a negative charge so, when they are generated, protons (with a positive charge) are also created. When the anode and cathode are connected to each other by a wire acting as an external circuit, the negative charges migrate between those two electrodes. Simultaneously, the positive charges migrate from the anodic region to the cathode through a wet system, in this case the soil. The cathode contains a catalyst that enables the electrons, protons and atmospheric oxygen to recombine to form water, thus completing the circuit and permitting an electrical current to be generated in the external circuit.
The P2P hub therefore generates electrical current from the combination of biological and physical elements. Each element of the hub is monitored separately, and members of the public can track the findings in real time, at a dedicated website http://www.plantsci.cam.ac.uk/p2p and on a computer embedded in the hub itself.
Margherita Cesca, Senior Architect of MCMM Architettura, the hub’s designer, is pleased that it has garnered so much interest. “This prototype is intended to inspire the imagination, and encourage people to consider what could be achieved with these pioneering technologies. The challenging design incorporates green wall and solar panels as well as glass, creating an interesting element which sits beautifully within Cambridge University Botanic Garden,” she said.
Bombelli added: “The long-term aim of the P2P solar hub research is to develop a range of self-powered sustainable buildings for multi-purpose use all over the world, from bus stops to refugee shelters.”
P2P is an outreach activity developed under the umbrella of the BPV (BioPhotoVoltaic) project working in collaboration with green technology companies Polysolar, MCMM, and Scotscape. The BPV project includes scientists from the Departments of Biochemistry, Plant Sciences, Physics and Chemistry at the University of Cambridge, together with the University of Edinburgh, Imperial College London and Cape Town University.
The innovative prototype solar hub was unveiled at the Botanic Garden during an event at the Cambridge Science Festival, Trap the light fantastic: plant to power, on Tuesday 10 March 2015.