Posts Tagged ‘electricity generators’

Engineers Tap Algae Cells for Electricity

With the help of photosynthesis plants convert light energy to chemical energy. This chemical energy is stored in the bonds of sugars they use for food. Photosynthesis happens inside a chloroplast. Chloroplasts are considered as the cellular powerhouses that make sugars and impart leaves and algae a green hue. During photosynthesis water is split into oxygen, protons and electrons. When sunrays fall on the leaves and reach the chloroplast, electrons get excited and attain higher energy level. These excited electrons are caught by proteins. The electrons are passed through a series of proteins. These proteins utilize more of the electrons’ energy to synthesize sugars until the entire electron’s energy is exhausted.

Now researchers at Stanford are inspired by a new idea. They intercepted the electrons just after they had been excited by light and were at their highest energy levels. They put the gold electrodes inside the chloroplasts of algae cells, and tapped the electrons to create a tiny electrical current. It may be the beginning of the production of “high efficiency” bioelectricity. This will be a clean and green source of energy but minus carbon dioxide.

Stanford University researchers got their work published in the journal Nano Letters (March, 2010). WonHyoung Ryu is the main author of this work. He says, “We believe we are the first to extract electrons out of living plant cells.” The Stanford research team created an exclusive, ultra-sharp gold nanoelectrode for this project.

They inserted the electrodes inside the algal cell membranes. The cell remains alive throughout the whole process. When cells start the photosynthesis, the electrodes attract electrons and produce tiny electric current. Ryu tells us, “We’re still in the scientific stages of the research. We were dealing with single cells to prove we can harvest the electrons.” The byproducts of such electricity production are protons and oxygen. Ryu says, “This is potentially one of the cleanest energy sources for energy generation. But the question is, is it economically feasible?”

Ryu himself provides the answer. He explained that they were able to extract just one picoampere from each cell. This quantity is so little that they would require a trillion cells photosynthesizing for one hour just to get the same amount of energy in a AA battery.

Another drawback of such an experiment is that the cells die after an hour. It might be the small trickles in the membrane around the electrode could be killing the cells. Or cells may be dying because they’re not storing the energy for their own vital functions necessary to sustain life. To attain commercial viability researchers have to overcome these hurdles.

They should go for a plant with larger chloroplasts for a larger collecting area. For such experiment they will also need a bigger electrode that could tap more electrons. With a longer-surviving plant and superior collecting ability, they could harness more electricity in terms of power.

Nanyang Technological University in Singapore to Build Renewable Energy Integration Demo Microgrid

Nanyang Technological University (NTU) recently announced it will be building a hybrid microgrid which will integrate multiple large-scale renewable energy sources.

The first in the region, the hybrid microgrid will test and demonstrate the integration of solar, wind, tidal-current, diesel, storage and power-to-gas technologies, and ensure these energy sources operate well together.

To be built under the new Renewable Energy Integration Demonstrator – Singapore (REIDS) initiative, the hybrid microgrid will be located offshore at Semakau Landfill and is expected to produce power in the megawatt (MW) range, which will be suitable for small islands, isolated villages, and emergency power supplies. It will be able to power around 250 HDB 4-room apartments, which together consume a peak of 1 MW.

This initiative is supported by the Singapore Economic Development Board (EDB), and the National Environment Agency (NEA). The S$8 million initial microgrid infrastructure will also facilitate the development and commercialization of energy technologies suited for tropical conditions to be developed by NTU together with 10 world leading companies.

“Sustainability is one of the major pillars of NTU’s research. We have been very active in clean energy research such as in tidal, solar and wind technologies and this new initiative will allow us to apply our research and integrate the different energy sources. In so doing, we hope to develop practical renewable solutions for the energy integration industry,” said NTU President Professor Bertil Andersson.

The initiative is expected to attract $20 million worth of projects over the next five years, in addition to the initial $8 million investment in infrastructure on the Semakau Landfill.

The ten energy and clean tech industry leaders who seek to be part of this effort include Accenture, Alstom, Class NK, DLRE, GDF Suez, Renewable Energy Corporation, Schneider Electric, Trina Solar, Varta and Vestas.

“NTU’s REIDS will serve as a strategic living lab for Singapore, encompassing a large scale microgrid with a plug-and-play setup that clean energy industry leaders can leverage to develop and demonstrate and diverse range of clean energy technologies,” said EDB’s Assistant Managing Director Mr Lim Kok Kiang.

The REIDS project is to be implemented in two phases. In the first phase, a microgrid facility will be built at the Semakau Landfill that will oversee energy storage facilities, solar photovoltaic panels and wind turbines. The hybrid microgrid will be designed to provide a full-scale test-bed for Singapore’s on-going energy research, working closely with scientists and engineers from both the public and private sectors.

A key problem posed by renewable energy sources is that of intermittent power supply. According to NTU, the hybrid microgrid aims to ensure a stable and consistent power supply through the integration of a variety of smart energy management and storage systems.

The second phase of the project will involve the development of a scaled-up tidal energy facility around Semakau Landfill and St. John’s Island, which will then be integrated with the first phase.

A key long term goal of the initiative is the development of microgrid technologies that can help provide electricity to overseas communities that do not have access to power. This is in addition to introducing new technologies that can stabilize power grids in urban communities. Both are widely regarded as critical needs across Asia.