Coming up: a new way of optimising your CSP plant
Next year will see the launch of a new service that will allow plant developers and operators to work out the best way to make a profit on their design and operations.
By Jason Deign
A new service that could lead to significant improvements in CSP-with-storage plant design and operation is due to be launched early next year.
Currently under development at the KTH Royal Institute of Technology in Sweden, the consulting service will use a specially designed software tool called DYESOPT to provide a range of optimised plant designs for particular markets.
Taking a plant in Upington, South Africa, as a reference case, the developers believe the system could help boost internal rates of return from a sub-optimal level of 5% or 10% to as much as 23% or 24%.
DYESOPT, which stands for DYnamic Energy Systems OPTimiser, will draw on an immense module library called SOLCONTROL that manages environmental parameters such as direct normal irradiation and market economy characteristics such as spot prices or incentives.
Based on this information, it can provide guidance on how much storage to include, and how to operate it, to maximise returns for a given market.
The system can even help plant owners adjust the operation of existing projects to meet changing market requirements, such as when a feed-in tariff (FiT)-based payment system is replaced by a different form of incentive, as has happened in Spain.
DYESOPT is being developed as work package within the Tesconsol project, a consortium between KTH, the oil company Total, the Catalunya Polytechnic University, the Spanish utility Gas Natural Fenosa and Tecnalia, a private applied research and development centre.
Elsewhere, Tesconsol is also developing a molten salt optimisation system, as previously revealed in CSP Today.
Plant designs
The need to adapt plant designs to market conditions has been highlighted through cases such as Gemasolar in Spain. This was originally conceived to provide base-load capacity with FiT payments.
But following a change in legislation in Spain all renewable plant owners now have a limited, fixed level of return from the government and are being forced to claw back some semblance of profit from the spot market.
These differing modes of remuneration can affect the way a plant is designed and operated.
For spot-market remuneration, for example, instead of round-the-clock operation it may be more cost-effective to build a plant with just enough storage capacity to shift loads towards the evening demand peak.
And for plants already in operation, it may determine how much power is released to the grid and how much is stored at particular times.
In particular, for spot-market pricing, DYESOPT can calculate the optimum plant configuration and operation based on an analysis of stochastic movements in energy prices over a historic period, say 30 years, and cost functions for the market in question.
For given plant configurations, customers will be able to predict key economic parameters such as levelised cost of energy, internal rate of return or cash flow.
Rafael Guédez, who is developing DYESOPT within KTH’s Energy Department, says the service will help owners solve queries such as what plant will be most profitable for a given level of capital expenditure (cap-ex).
Maximising income
“Plant owners often have seemingly contradictory objectives, such as maximising income while minimising cap-ex or op-ex,” he says. “So what we provide as an answer is not a single design but a whole range of optimum designs for different cap-ex and op-ex levels.”
The service is set up for power tower and parabolic trough plant designs only, but can also be used for traditional thermal and cogeneration power plants, which is where it will be commercialised initially in Sweden.
Nevertheless, by comparing the range of plant designs for parabolic trough with those for power tower, a developer could choose which technology would be most appropriate for a given location, taking also into account factors such as bankability.
The Tesconsol projects have been under development for the last four years and are due to be released commercially in February 2015, albeit that the DYESOPT tool will be worked on for a bit longer to improve its usability.
In the meantime, the tool will not be offered on a standalone basis to customers but will be made available as part of a wider consultancy offering to the CSP industry, delivered through a KTH spinoff called Power Solutions Europe.
The company will also provide full market modelling to determine optimal technology mixes and individual system operation on a regional-network basis.
Tesconsol is notable for being the only CSP project currently supported by the European Institute of Innovation & Technology’s InnoEnergy Knowledge and Innovation Community (KIC), a private sector body that uses public funding to help start-ups with major potential.
The funding lends a fair amount of credibility to the project since competition for KIC InnoEnergy sponsorships is fierce. “In the last two years, 50% of our start-ups have raised a total of €11.6 million from third parties,” says KIC InnoEnergy’s chief executive officer, Diego Pavia.
“We produce game-changers.”