Contrary to what the terminology suggests ‘solar thermal energy’ is not a recent development and it is certainly not something that has just been invented as another answer to reduce greenhouse emissions. According to the Renewable Institute for Sustainable Research, the first solar powered engines were constructed back in the 1860s by a couple of French mathematicians. During the past 30 years a number of solar thermal plants have been built and operated around the world to produce guilt-free electricity. However, the technology has been rapidly evolving in recent years and Australia has perfected the technology to make it commercially more viable.

Unlike wind power or solar photovoltaic panels, which generate electricity directly, solar thermal power uses mirrors to concentrate the sun’s energy onto a receiver and create heat, which can then be used to produce steam to run a turbine and generate electricity, in the same way as a conventional coal-fired power station. The other advantage of solar thermal technology is that it can be stored very efficiently in large tanks of molten salt and then be dispatched to generate electricity at any time of the day or night, making it in effect base load solar power.

The way solar thermal energy plants work is by focusing the glare of the sun’s rays on a central location –usually on a tall solar tower- to create heat, which is then turned into electricity. The concentrated heat is extreme between 500-2000 C and it could easily melt metal. Due to various heat exchange processes involved –which were further advanced in Australia- the water eventually turns to steam, powering the turbines at the base.

Various methods exist to concentrate the solar radiation, including parabolic troughs, power towers with mirrors that track the sun (heliostats), parabolic dishes, and Fresnel reflectors (these consist of multiple flat mirrors). Each technology differs in the way that it concentrates the solar energy, but they all track the sun to maximise energy capture and produce heat, which is then converted to electricity.

These technologies are at different stages of development and each has its own advantages and disadvantages. It is fair to say that parabolic troughs are the most mature, having first been installed at utility scale in the 1980s; although the other types may ultimately prove cheaper due to their inherent design advantages. These technologies have been successfully used in the USA and Spain since the 1980s. But the Australian National University has re-designed the dish for optimisation for manufacturing and mass production with mirror panels that should be able to concentrate the sun at least 2,000 times.

Solar Thermal Uptake in Australia

Australia has large areas of high solar intensity and little rain, where large concentrations of renewable energy power stations could be developed. In fact the Australian continent has the highest average amount of solar radiation per square meter per year of any continent on the planet ranging from 1500 to 1900 kWh/m2/year. In other words Australia is better-suited to this technology than any other country in the world, including Spain who is expecting to operate 60 solar thermal plants by 2013.

Peter Meurs (Managing Director of WorleyParsons-EcoNomics) has said that establishing advanced solar thermal centres could allow Australia to exceed the 20 per cent renewable energy target by:

• Facilitating the commercialisation of developing renewable energy technologies.
• Triggering the development of domestic solar thermal component manufacturing.
• Enabling Australia to become a world leader in these technologies.
• Allowing the construction of larger scale solar thermal power stations over time.

Wizard Power is also part of the same consortium who has been trying to commercialise big dish technology in Australia for the past five years. Their unique technology was developed by the Australian National University’s solar thermal group over the past 40 years who have perfected ‘the big dish’ and they’ve also figured how to best store the sun’s energy thermo-chemically. It appears that Wizard Power may be getting some support from the federal government in the form of $60 million towards a $230 million solar plant it’s building in South Australia. Wizard Power suggested Whyalla in South Australia as an ideal place to establish large scale solar facilities, because of the climate and the number of large scale resource projects requiring power. Australia’s very first solar oasis in Whyalla is going to provide enough electricity to power the town of Whyalla and also to provide power to the neighbouring steel works. In total it’s capable of powering approximately 9000 average homes or replacing something in the order of 17000 motor vehicles on the road each year in terms of carbon emissions.

There is no reason why Australia couldn’t match the Spanish government’s commitment who is expecting to cover 12 percent of its primary energy from renewable sources by the end of this year. Spain is the fourth largest manufacturer in the world of solar power technology and exports 80 percent of its production to Germany. Australia cannot quite export electricity to other countries but we could export our expertise in this technology to build solar thermal plants in other countries. At the same time there is no reason why 30 solar thermal plants could not provide 40 per cent of Australia’s renewable energy needs by 2020-according to WorleyParsons. But to achieve this goal, action must be taken today.

References:

http://www.npr.org/templates/story/story.php?storyId=13826548)
http://www.abc.net.au/insidebusiness/content/2010/s2925759.htm
http://ecogeneration.com.au/news/advancing_solar_thermal/002019/
http://ecolocalizer.com/2008/04/12/mega-solar-the-worlds-13-biggest-solar-thermal-energy-projects/
K. Lovergrove and M. Dennis Solar Thermal Energy Systems in Australia 2006 International Journal of Environmental Studies (www.tandf.co.uk/journals)

I caught up again today with David McInnes, Group Manager Environment for Linfox - you can find the interview here. Linfox have cut their greenhouse gas emissions by 28% per km since 2006/07. They are aiming to cut their emissions by 50% by 2015. I find this tremendously refreshing and a great example for other companies to follow. 

The 28% reduction has cut fuel costs by $18 million annually compared with what they would have been with no action. Most of the savings have come from what David calls cultural change, the process of engaging with staff and getting them committed to minimising their environmental impact at work. The company is putting all its drivers through its Eco-Drive program, the single largest source of its savings. The Eco-Drive program has now been translated into six languages by Linfox.

When Linfox started on its greenhouse gas saving program back in 2006/07 it didn’t do a dry cost-benefit feasibility study, rather its board took the attitude that as a large contributor to transport emissions it had a responsibility to act. It set a target of a 15% reduction by 2010, not knowing how to achieve that, but putting faith that by going through a structured process of cultural change the results would be achieved. Their faith in this process has certainly paid off.

Its modelled its change process on the eight step change model developed by Harvard University academic John Kotter, who has written several books on the process of organisational change.

The first step of Kotter’s process is to create a sense of urgency. Linfox created this by focussing on the climate change science. Part of this involved commissioning a series of mindmaps by West Australian artist Jane Genovese, one of which which can be viewed by clicking on the link below.

mindmap-climatechangeimpacts

The Intergovernmental Panel on Climate Change says that greenhouse emissions need to be reduced globally by between 25% and 40% by 2020 on 1990 levels to limit global warming to no more than 2 degrees.  David believes that this target can be achieved, and Linfox is a great example of how business can lead the way.

A British government office has taken a radical step to reduce energy usage by installing timing switches in their toilets. In itself there is nothing unusual about this but staff in the West Midland reported that they have been often left in the dark after ten minutes when all the lights are switched off automatically in the cubicles.

The government workers explained that they feel humiliated and degraded as they often have to fumble and stumble in the dark struggling to make themselves decent before they can make their way back to the switch located near the entrance. The government employees complained that this is going too far since they were already complying with requests to switch the lights off in the toilets as they were leaving. The government bureaucrats believe that this is an undignified and possibly unsafe practice implemented in a misguided attempt to reduce energy use.

In response to their concerns a government spokesperson defended the timed toilet light switches; stating that they save both money and energy. She asserted that the government has introduced a range of measures across government buildings in order to reduce avoidable energy consumption and are continuing with similar works elsewhere. It is expected that these energy saving measures will be applied to all health, justice and education buildings in the Midlands. (Reported in the Daily Telegraph and reproduced in MX 31st March 2010).

Is this going a little too far? We will let you make up your own mind. However, we would probably recommend occupancy sensors in similar situations that could detect people’s movement or sensors that combine sound detection as well to avoid unexpected surprises. Toilet lights are one of the most pointless energy wasters in many buildings as the lights remain on all day or even 24/7 if forgotten. Numerous sites -especially government buildings- that we have audited implemented this strategy without complaints.

The Elithis Tower in Dijon, France, consumes just 20 kWh/m2 and was designed to cost no more than a conventional office buildings. The February issue of Ecolibirum, the magazine of AIRAH (Australian Institute of Refrigeration, Air Conditioning and Heating) reported on this building.

It is a 10 storey building of around 5,000 m2, with solar panels covering the rooftop. A “light shield” allows light but not radiant energy into the building. Low environmental impact materials have been used in its construction.

This is an extraordinary achievement, and is an example of human ingenuity rising to the climate change challenge. Most office buildings of that size would consume over 200 kWh/m2, and a very efficient building around 60 kWh/m2.

The Elithis Tower is the first building that I am aware of that beats the 30 kWh/m2 we achieved in the CarbonetiX office in 2008. In 2009 our emissions crept up to 33 kWh/m2, probably due to the introduction of additional computer monitors and staff countering the savings from skylights we installed at the end of 2008.

The Elithis Tower sets a great standard which I hope inspires further great engineering and design to make low or no energy use buildings the norm rather than the exception.

Last year VECCI - the Victorian Employers Chamber of Commerce and Industry – undertook a survey of business attitudes to climate change.

A surprising – and very disappointing result – was that many businesses believed they had done all they could do to minimise their energy use and carbon footprint.

This self-limiting belief means that these businesses are wasting money and energy, and producing greenhouse gases – needlessly.

One of our customers, who has already cut their energy use by up to 40% across a range of facilities, had us do a quick search for further energy saving opportunities late last year. This organisation is well known as being a leader in energy conservation and saving. Were we able to identify further opportunities to reduce their energy use, within their payback period? The answer to that is a resounding YES.

Henry Ford had a great saying which I love to quote. “If you think you can, or you think you can’t, you’re right.”

If you turn all your computers off at the end of the day and don’t leave lights on in empty rooms you might think you are doing all you can to save energy. But that would be wrong. For example, you probably still have opportunity to delamp (remove excess lamps in areas that are too bright), and to save computer power through aggressive power management settings. And that’s without investing any capital! If you have some money to invest you can save any more, and get a return on investment the banks would kill for.

If you want to cut your energy use, you can!