Here are a few of the questions we get asked most frequently about the moss table:

What is the Moss Table?

The Moss Table is a concept product which demonstrates a potential future application of BPV technology.

What is BPV?

BPV stands for Bio-Photo-Voltaic. BPV devices generate electricity from light energy by exploiting the photosynthesis of living organisms such as cyanobacteria, moss, algae and vascular plants. More information about BPV technology has been published in Catalyst Magazine (Bombelli and Driver, 2011), and the Journal of Energy and Environmental Science (Bombelli et al, 2011; McCormick et al, 2011).

What does the Moss Table do?

The table incorporates an array of BPV devices which generate electricity. At present the energy generated by the table is not used to power anything. Instead an animation has been created which responds to the current output of the table. In this way people can ‘see’ the energy produced by the table as seen in this video: http://www.youtube.com/watch?v=Tw7JcOHNZlY&feature=g-all-lik

Does the moss power the lamp?

No, it cannot currently generate enough energy to power the lamp. BPV technology is at an early stage of development and there are significant technical hurdles to overcome before products like the table are commercially viable.

Does the moss power the digital chock?

Yes – It can power small devices like a digital clock using some of the units operating inside the Moss Table.

Why does the table incorporate a lamp?

The table is a concept product which demonstrates a potential future application of the technology. The idea behind the table is that energy generated during the day would be stored in a battery. In the evening this energy could be used to power a lamp.

How much energy is produced by the Moss Table?

Currently the table can produce about 520 Joules (J) of energy per day. A typical laptop requires about 25J per second, so in a day the table would produce enough energy to power a laptop for just 20 seconds!

Can the Moss Table deliver more energy in the future?

Currently, the moss generates about 50 milliwatts per square metre (mW/m2). Scientists anticipate that future devices may be able to generate up to 3W/m2 (Strik at al., 2011). Low-energy consumption laptops are being developed (e.g. the XO-1, manufactured by Quanta Computer) which could operate at as little as 1W, meaning that a plant-powered laptop could be possible in the future. In this futuristic scenario, the Moss Table could power a laptop for over 14 hours.

How does the Moss Table work?

Photosynthesis is a process by which plants and algae convert carbon dioxide from the atmosphere into organic compounds using energy from sunlight. The plants use these organic compounds (like carbohydrates, proteins and lipids) to grow. When the moss photosynthesises it releases some of these organic compounds into the soil, which contains bacteria. The bacteria break down these organic compounds, which they need to survive, liberating by-products that include electrons. These electrons are captured by conductive fibres inside the Moss Table and put to use. In this way the devices harness energy which would otherwise be wasted. This is achieved using an array of 112 ‘moss pots’, which are bio-electrochemical devices. This means that they convert chemical energy into electrical energy using biological material. Each one generates a potential of about 0.4-0.6 volts (V) and a current of 5-10 microamps (µA).

How can the efficiency be improved?

There are several possibilities including:

Increase the rate at which the moss excretes organic compounds into the soil.

Increase the rate at which the bacteria break down the organic compounds and produces electrons.

Improve the electrical connection with the bacteria.

Reduce the internal resistance of the device.

How long will the moss stay alive?

If the moss has access to water and light, it should continue to grow and generate energy. However, we have not yet conducted an experiment to measure the durability of the moss. We have had one device operating for 3 months quite happily.

Is the moss inside the table special?

No, the table uses many different types of moss. No experiments have yet been conducted to determine if some mosses work better than others. BPV devices can also be constructed using cyanobacteria, algae and vascular plants.

Who is researching BPV?

Research into BPV is funded by the Engineering and Physical Sciences Research Council (EPSRC) and is led by Professor Christopher Howe from the Department of Biochemistry, Professor Alison Smith from the Department of Plant Sciences and Doctor Adrian Fisher from the Department of Chemical Engineering and Biotechnology at Cambridge University; and Doctor Petra Cameron from Bath University.

Why was the Moss Table made?

The moss table was produced as part of a research project called “Design in Science”, which set out to explore how designers might be able to support scientific research. The purpose of the table is to:

Demonstrate through a familiar domestic object, that BPV technology has potential applications in our everyday lives.

Allow the scientists working on BPV technology to disseminate their research to a wide audience.

For more information on Design in Science, see “Design in science: Exploring how industrial designers can contribute to scientific research” (Driver, Peralta & Moultrie, 2012)

How big is the Moss table?

The moss table is 1 metre in diameter and 1.2 metres high.

What is the Moss Table made of?

The body of the table is made from ABS plastic. The lamp shade and top surface of the table are made of acrylic, as are the ‘moss pots’ inside the table. The pots include stainless steel connectors, carbon electrodes, soil, moss and water!

What are the bubbles behind the Moss Table?

This is an animation that provides a graphical representation of the current produced by the table. We created this animation to visualise the behaviour of the moss.

Can I buy the Moss Table?

The Moss Table is a concept product and was not originally designed to become a commercial product; however there are plans to design and develop commercial products incorporating biophotovoltaic technology. For example, a digital clock powered by moss is currently in development.