Future Fuel - That's a Wrap!

It is going to be very strange not to scour newspapers, websites and journals looking for new projects and research to blog about. I feel I have begun to read things though a pair of "blog potential" glasses.

At the start of the blog I decided I wanted to investigate three main areas: energy demand, energy sources and the future for fuel supply. With growing population and more importantly increasing living standards it is certain that the demand for fuel is going to increase. Particularly in cities and rapidly developing countries the demand increase could be exponential. I looked at the current sources of energy: focusing on gas, oil, nuclear, coal and renewables. Over the next 50-100 years we are likely to see a shift towards natural gas and nuclear with many experts predicting that oil supply has peaked and will now decline. Growth of renewables will probably continue at the slow steady pace but the next big milestone will be the commercial scale of hydrogen fuel cells.

Energy Supply

After a few weeks of writing the blog I kept finding articles about new inventions that were being researched but weren't necessarily producing industrial scale amounts of electricity. So I introduced the "Technology Idea of the Week" section alongside my focus sections on different energy sources. They ranged from algae and artificial leaves to mining meteorites and hydrothermal vents. It was fascinating investigating these new ideas and seeing them being turned into business. There are definitely some I will follow over the next few years! One of the biggest lessons I have seen through every section of this blog is that energy supply is big business and it needs to be profitable. New, renewable, clean technologies have to be more profitable if they are going to be successful. I loved the wordle on Helen's blog (gaiaocean.blogspot.co.uk) and was intrigued to see what the one for my blog would be. With the words energy, solar and hydrogen jumping out I think it summarieses it very well!

Energy Enquiry most used words - produced by Wordle

At the start of this investigation, I wondered about what ingredients do you need to make a successful blog? Well informed content, interesting new topics, amusing titles, bad puns, pictures and videos have all played a part for me. By far the most important aspect has been writing on a topic that you are really interested in. Writing becomes enjoyable rather than a chore and you feel a sense of responsibility to provide accurate and interesting posts. My search for the right balance of ingredients reminded me of the Roald Dahl book: George's Marvellous Medicine: I think I have discovered the recipe that works for me!

George's Marvellous Medicine

Unobtainium

The news headlines seemed more like the plot of Avatar rather than an actual business. Mining asteroids? Really? Are you absolutely sure? With some big name supporters like James Cameron and Richard Branson the projects seemed to have a lot credibility and definitely the financial backing (The Economist March 2012).

The Economist March 2012

Some new investigations have brought this idea crashing back down to reality. Research by Harvard physicist, Dr Martin Elvis, states that there are only 10 near earth asteroids that are actually economically viable to mine (BBC News January 2014). The study focuses on estimating the concentrations needed to make asteroids viable to mine an then assessing how many fall into this category. Not nearly as many as we originally thought is his argument. However, there are a lot of uncertainness in the data. Possibly the most important uncertainties are the estimates of Platinum and Palladium, even small increases in the concentrations effect the concentration range from $800 million to $8.8 billion (Elvis, 2013, Planetary and Space Science).

Eric Anderson, co-founder of Planetary Resources, picks up on some issues he has with the paper. Firstly, the conservative estimates are partly because the paper only considers one type of asteroid (M-type). Elvis argues that we don't know enough about the other types to assess their economic resource potential. Secondly, we have only discovered 1% of the asteroids in the solar system (BBC News January 2014). Again Elvis states that this doesn't matter because he is only considering near earth asteroids that are actually reachable.

I find the whole idea of mining in space very exciting and hope that the project does continue to go ahead. However, Elvis and Anderson do seem to agree on one aspect and that is the level of unknown variables that make it difficult to predict profitability. If it doesn't go so well, I'm sure this cheerful little group of actors would make a great alternative cast for a lower budget version of Avatar Two...

The Smufs

Harvesting Solar Energy - Artificial Leaves

Having had a quick look at solar energy already, one of the key issues is the efficient production of energy from solar cells using widely available materials. Scientists at Harvard University have been addressing this.

The Artificial Leaf 

This carries out the same processes as in nature but it allows for collection of oxygen and more importantly hydrogen which can be used as a fuel. The leaf is made of a silicon wafer: one side produces oxygen and the other produces hydrogen from photosynthesis. The the important break through with this research is that cheap and widely available metals have been used as catalysts in the reaction, instead of platinum which how it was originally achieved (Reece et al, 2011, Science). As it really highlights in the paper, the most important development is the cheap and widely available materials that are used in the process.

Harvard Professor and one of the main authors on the paper, Daniel, Nocera, explains the process in this Horizon clip. 

No external wires or controls are needed, the silicon chip just has to be placed in water. This is what it actually looks like, with some real leaves in the background in case you hadn't seen them before... More information can be found on the MIT News Site

The artificial lead - image from MIT news

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! 

'Here comes the sun'

Before university I spent a year working with a chemical engineering company making ink. I was a little disappointed to discover that this did not involve farming squid but instead mixing up various combinations of chemicals. I specialised in conductive inks and by far our the fasting growing demand was for solar cells. This hardly makes me an expert but means I have an interest in the area!

Firstly, some basics. Solar cells (or photovoltaic cells) generate energy by the photovoltaic effect. Light from the sun, made up of photons, hits the semiconductor in the solar cells. This excites electrons in the atoms which make up the semiconductor and releases them from the shell. There is a electrical gradient in the semi conductor which attracts the released electrons which then flow: generating electricity (physics online).

Potential energy - image from Solar Spark

The potential solar energy available is enormous: 120,000 TW per day compared to the global energy use of 15 TW per day (solar spark). However, this is the total sunlight hitting the earth so if we wanted to use it we would have cover the earth in solar cells and have them all work with 100% efficiency. This is not possible but it does demonstrate just how much we could utilise solar energy.

Now back to those squid...

Technology Idea of the Week

Finding alternative energy sources to produce cheaper electricity for households and businesses is becoming a huge business but what about carbon intensive industrial processes as well?

Cement Processing 

Making cement is one of these intensive industrial processes. After water, cement is the second most consumed substance on the planet: each person uses about 3 tonnes per year (Environment Publications, UNEP, 2010). It is one of the main materials in essentially every construction project including buildings, bridges, reservoirs and roads. We often do not see the extent to which concrete is used in construction for example The Shard has concrete foundations reach down 53m: approximately 1/6 of the buildings height (Ingenia Engineering, 2012). In 2010 the global production of cement produced about 3 billion tonnes of CO2, accounting for 5% of global emissions (TIME, 2010). The diagram below shows a very simplified outline of the process where raw materials (gypsum/limestone) are heated in a kiln to produce cement and give off CO2 emissions.

Cement Production - image courtesy of CO2CRC

The Energy Demands 

This is a summary of the main energy demands - summarised from Madool et al 2011, Renewable Energy Reviews 

• Extraction and crushing of raw materials before going into the kiln (green on diagram below)
• Heating the kiln to ~1440°C (purple on diagram)
• Final grinding of the clinker into a fine grey powder which can be added to fluid to make cement (blue on diagram below)
• Other auxiliary needs such as transportation of raw materials (red on diagram) 
• On average, producing 1 ton of cement produces just under 1 ton of CO2

Energy Distribution in Cement Manufactoring - Madool et al 2011, Renewable Energy Reviews 

New Innovations 

1. Using the by product - one way to reduce the energy costs of cement which has become common in the last few years is to use the 'slag'. This is the waste product from the production of Portland Cement and was previously thrown away creating the distinctive 'slag heaps'. However, it is now often used in combination with pure cement for example the foundations of The Shard use 70% slag and only 30% Portland Limestone (Ingenia Engineering, 2012). This dramatically reduces the cost of building and the CO2 emissions. 

2. Waterproofing cement - cement is rarely recycled because as water seeps in it reacts with the calcium carbonate (limestone) and causes it to slowly breakdown. This is the same chemical reaction that forms limestone caves, karst landscapes, stalactites and stalagmites. If we could waterproof cement and prevent the breakdown we would not have use new cement in every building. This is what the company Hycrete are aiming to do. A hydrophobic mixture is poured over the cement to reduce the absorption of water to less than 1% (Hycrete Admixtures). This is a bit like pouring oil over it except cheaper and more sustainable!

3. New Formulas - both the above solutions really help to reduce the energy demands of cement production but the ultimate goal would be to produce carbon neutral cement. This is what Novacem is aiming to do. Based on research from Imperial College London, a new type of cement based on magnesium silicate rather than calcium carbonate has been created. This absorbs CO2 as it solidifies: almost three times as much than the traditional formula. This could actually result in the cement industry being a net absorber of CO2 rather than emitter (Imperial College, Novacem Research). In addition, the by products of production can be used and it is waterproof. Almost too good to be true! 

Tackling big industrial processes is a really important part of finding energy solutions. It would take an awful lot of wind farms to see the same benefit as creating a carbon negative cement.  

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.