By Rikki Stancich in Paris

As part of its  Au$5.1 billion expanded Clean Energy Initiative (CEI), the Australian government has committed Au$1.5 billion to support the construction of up to four large scale, grid-connected solar power stations in Australia.

Eight candidates have been shortlisted from the original 52 applications submitted. Of these, four use CSP technologies, with the remaining four based on photovoltaic technologies.

Novatec Biosol recently made headlines with its 30MW PE2 plant in Spain coming online and with the announcement that it has made the shortlist for Australia’s government-backed Solar Flagships programme.

CSP Today catches up with Novatec Biosol's recently appointed CEO, Denis Orwig, to gain a shortlisted candidate's perspective on Australia's Solar Flagships funding programme and to gauge Australia's committment to breaking its fossil fuel habit.

CSP Today: At this stage, Australia seems to be embracing the hybrid and ISCC approach over stand-alone utility-scale CSP plants (in view of Transfield Holding/Novatec's augmentation project and Ausra-Areva's Liddell and Kogan creek hybrid projects). In your view, what is the reason for this?

Dennis Orwig: There are both stand-alone and hybrid developments in Australia at present. The federal government’s solar flagships programme is based on solar only with a maximum possible gas fired component of 15%, so the 4 short-listed CSP bids for this programme are solar only.

Augmentation, ISCC / solar boost and fuel saver integrations of solar and other fuel projects make a great deal of economic sense, so projects being proposed outside of the solar flagships programme are mostly put forward on this basis. 

This is because solar-only power stations only run when the sun is shining, so they can only use around 20% of the capacity of the investment in the balance of plant, turbines, generators, condensers, and grid connection.

While it is possible to implement storage to increase this ratio, storage is still expensive and may not represent the most efficient use of capital to decrease total emissions. 

By contrast, using solar steam to replace or augment fossil fuel steam in a hybrid plant can mean that the investment is being used round the clock. 

In time, the capital cost of heat storage technology may come down to the point that it is possible to economically generate base load power round the clock, but we are not at that point yet.

Liddell is  a fuel saver / solar boost proposal for adding a solar field to a coal fired existing power station, thereby reducing the amount of coal required for a given power output when the sun is shining.

CSP Today:  What are the advantages of Fresnel over dish and parabolic trough technology?

Dennis Orwig: Fresnel has significant advantages over parabolic trough. These include significantly lower capital cost, more efficient land use, less parasitic load and in the case of Novatec’s technology, an ultra low water use mirror cleaning system. Fresnel systems are generally more scalable and simpler to build. 

The lower use of land, water, raw materials (mostly glass and steel), earthworks and concrete in foundation make the overall environmental impact of linear Fresnel technology much lower. 

Fresnel is more than competitive with parabolic trough due to its much lower cost at current relatively low temperatures and consequently low thermal to electric efficiency.  Further developments in the technology will only increase this level of efficiency.

CSP Today: Is Australia's remote geography more accommodating of Fresnel technology than of other types of CSP technology? 

Dennis Orwig: The advantages of linear Fresnel technology extend to both remote and non-remote sites. Some advantages of the technology, which may be particularly advantageous at a remote site include:

• Low water utilisation
• Reduced material use and improved component transport efficiency
• Lower work force
• No need for gas

Lower water utilisation can be particularly advantageous at remote sites.  Novatec’s technology uses about 2 percent of the water to clean the mirrors when compared with parabolic trough cleaning systems, allowing sites to be used where there is no water connection. 

Reduced material use and improved component transport efficiency are also more significant at remote sites. Novatec’s linear Fresnel technology uses about 30% of the material used by parabolic trough, and can be assembled by a much smaller labour force. 

It is also more feasible to manufacture large or small fields at remote locations using Novatec’s scalable automated production technology. 

Novatec’s linear Fresnel plant PE1, which has been in commercial operation in Spain since March 2009 operates without the use of gas, as will its 30MW PE2 plant, which has Swiss energy utilities EBL and IWB as investors and is currently under construction. 

By contrast typical parabolic trough steam cycles make use of gas to maintain operating temperature and pressure overnight to avoid much longer steam cycle start up times. This is significant where there is no gas supply at a remote site.

CSP Today: What are the biggest challenges currently facing CSP project developers in Australia?

Dennis Orwig: Certainty over the system which will be implemented to reduce carbon emissions will greatly assist all participants in the energy market, and in particular renewable energy developers. 

A greater recognition by governments of the better economic value in greenhouse emissions reductions possible through hybridisation would make a significant difference.

CSP Today: In your view, does the Solar Flagships shortlist include the best possible candidates/options?

Dennis Orwig: It is difficult for us to comment conclusively as we do not have the details of all the submissions made nor the full details of the short listed proposals. 

However, from our understanding the government was looking for technologies that it could be certain could be delivered.  Parabolic trough technology is proven but expensive. 

While Linear Fresnel technology has less operating history, it now has sufficient operating experience to allow potential lenders, investors, utilities and their technical advisers to observe the technology at work in commercial, operating power stations. 

Technical due diligence on Novatec’s 1.4MW PE1 plant was completed by Lahmeyer and Fichtner and on the basis of this due diligence, construction has been commenced on PE2, a 30MW plant based on Novatec’s technology.  

Tower technologies on offer are not proven at scale and still have to demonstrate that significant technical challenges can be solved on an operating basis. Although tower technologies hold out the promise of higher temperature steam, which may lead to higher thermal to electric efficiency, they are unproven in operation at high temperatures. 

Even if these technical issues can be solved, dual axis tracking solar fields are more expensive to build than single axis tracking, and this additional cost will possibly more than eliminate any higher thermal to electric efficiency benefit.

To respond to this article, please write to the editor:

Rikki Stancich: rstancich@gmail.com