Technology idea of the week

Olivine: a magnesium iron silicate found in the mantle

Olivine - image from Web Mineral Data

Researchers from University of Lyon have discovered a way to split hydrogen gas from water, using rocks.

Process - information from the original paper Andreani et al, American Journal of Mineralogists, 2013

1. A mixture of olivine minerals and water are heated to around 300 degrees Celsius
2. Small amounts of ruby (aluminium oxide) are added: a source of aluminium atoms
3. Mixture is put into a pressure cooker formed of two diamonds that can increase the pressure to 2000 atmospheres! This is about twice the pressure found at the deepest parts of the ocean. 
4. The olivine removes one oxygen and one hydrogen atom from the water molecules to form the mineral serpentine. This releases a spare hydrogen atom that could be used to generate energy. 

This is the same process that occurs over geological time scales as rocks are buried to form oceans. Serpentine is found in many locations globally. 

Opportunities of this process

• It is a low carbon production of hydrogen which could be used in hydrogen fuel cells (BBC news December 2013)
• The reaction is very quick, much quicker than expected. Breakdown of one crystal in a lab took a number of hours whereas it was expected to take weeks (Andreani et al, American Journal of Mineralogists, 2013)
• Serpentinite absorbs CO2 by carbonation. Therefore this process has two benefits: the production of clean energy and the removal of CO2 from the atmosphere (Physics Online December 2013). 

Finally, as well as the opportunities for a new energy source, this discovery hugely progresses our understanding deep sea process. Life on the sea floor is dominated by organisms that rely on hydrogen and our new understanding of this process helps explain the vast quantities of hydrogen that are available to them. I am interested to see how this research develops over the next few years! 

Oh I do like to be beside the seaside

Any dreams of a white Christmas this year unfortunately didn't come true. Instead the UK suffered flooding, thunderstorms and power cuts. What is the possibility of using this tidal power and will it provide a economically and socially viable solution?

Machine Current Turbines - courtesy FPS

Most of the research in tidal engineering focuses on harnessing fast moving, tidal streams such as the Severn Estuary which are enhanced by topography such as headlands therefore can provide more energy. There are currently only 15 projects worldwide (Denny, 2010, IEEE).

Here is a brief summary of the benefits and cost of tidal power, summarised from Denny, 2010, The Economics of Tidal Power, IEEE

Benefits - The Ireland Example 

• The capacity credit: the amount of conventional (fossil fuel) generation that could be offset by tidal energy. This is was measured for Ireland and estimated to be about $9 million saving per year and could provide 18% of the countries energy sources. 
• Saving money due to reduced emissions of harmful gases which could save $16 million per year for Ireland. Assuming a price of $30 per ton of CO2, $150 per ton of SO2 and $3000 per ton of NOx. 
• Reduced fuel costs to consumers due to lower running costs of the tidal barrage ($39 million per year). Tidal has a particular advantage over over renewables because it is reliable and fairly predictable.

Costs - The Ireland Example

• Variations for energy demand throughout the day mean that energy generators have to be able to ramp up and down power supply. This requires starting and stopping different components such as turbines and boilers. In a tidal barrage, this can cause huge stress on the equipment and reduces the life expectancy therefore increasing the cost. 
• Variations in tidal maximums require careful monitoring and cycling to ensure there is not a power surge. This could cost anything up to $23 million per year for Ireland!
• Building of the tidal barrage and laying cables on undulating sea floor can be very difficult and increase start up costs.

Total cost analysis from Denny, 2010, The Economics of Tidal Power, IEEE suggests that: 

Benefit = $64 million per year, cost = $23 million per year 

Therefore a net positive of $41 million per year 

However, this DOES NOT include the capital investment costs. The cheapest plan currently available to Ireland is $700,000 per MW of power produced. For energy production to just break even the costs would have to be $530,000. Therefore the current plans for tidal energy for Ireland would not be profitable. 

Ireland is recommended as one of the most suitable locations for tidal barrages and despite this this current plans would not be in profit. Energy production is business. This isn't good business. 

Technology Idea of the Week

"All I've heard from you lot so far is a lot of hot air, so in the interests of climate change: you're fired!"

A classic Lord Sugar quote from the BBC series The Apprentice (top on liners blog). Nice to see a acknowledgement of environmental change as well! Business plan competitions have become quite a major event for entrepreneurs over the last few years and are a great way to get a head start in business, unless of course you make a fool of yourself on The Apprentice. The CleanTech Challenge is a competition run by University College London and London Business School which looks for ideas which provide a "sustainable environmental benefit". So for this weeks tech innovation I am going to look at the 2013 winners of the CleanTech Challenge. 

The Power Window - Delft University of Technology 

• A luminescent foil is placed over a glass window
• The foil absorbs photons of light and scatters them towards the edge of the window 
• Solar panels around the window frame absorb the light and generate electricity
• The students at Delft University of Technology developed a new material which helped improve the efficiency of this process by a factor of five
• For more information check out the Delft TU Website or CleanTech Challenge. There is also an interesting video on the subject, link is posted below. 

A Solar Concentrator developed by MIT, similar to the Delft Invention

Delft TU Power Window YouTube Clip

It is really interesting to see the variety of business plan competitions that are focused on finding technological solutions to environmental and energy challenges. What is also interesting is that often these competitions are organised and funded by large engineering or energy companies as well as by research institutions. I think this is a really positive move for the green movement: by making it a business opportunity you can guarantee peoples interest and investment to make real change. I look forward to see what ideas come out of the competition this year! 

Technology Idea of the Week

Technological developments help determine the future of energy sources so I have decided to introduce a new feature in my blog: Technological Idea of the Week! Some of the ideas maybe in the start up stage, some of them maybe more in the creative stage! This will help to examine some of the new players in the energy market alongside the giants such as oil and nuclear power.

The Solar Chimney 

For my first edition in this series I am going to look at a project that takes a new approach to solar and wind power. What is particularly unique about this project is the way it combines different renewable technologies to help improve reliability and maximise power production. 

Image Courtesy of Solar Innovations

The Solar Chimney has two key components: a array of solar cells and a chimney with a turbine at the top. Air is heated at the base by the solar cells and therefore decreases in density and rises up through the chimney. This creates an updraught of air which will propel the turbines at the top of the chimney generating electricity. This can be seen in the diagram below which also demonstrates how this could be attached to houses and utilise pre-existing chimneys.

Image Courtesy of Solar Innovations

This idea has been around since the beginning of the 20th century and an experimental one was constructed in 1982 but then taken down due to concerns over collapse (BBC News, 20th November 2013). However, this idea has suddenly been given life again due the backing of Per Lindstrand who aims to build a 1km (yes 1km) high tower! He is famous for being the first person to cross the Atlantic in a balloon and has funding for this project from the 1851 Royal Commission (The Engineer, 19th November 2013).

Over the last thirty years there has been a lot of research into modelling solar chimneys to try and estimate how effective they can be. The chimney height and turbine head design have the biggest impacts on the efficiency of the solar chimney (Hamdam, Renewable Energy, 2011). Comparison of existing solar chimneys in Spain and Australia have allowed testing of the models to access their validity but there is much more research needed to make sure we use the best design to maximise efficiency (Nizetic et al, Energy Journal, 2008).