Solar steam to be focus of academic report

Renewable energy technology developed by Bourne-based Lark Energy, part of The Larkfleet Group of Companies, is to be the subject of a research paper being written by leading academics.

Dubbed ‘solar steam’, the Larkfleet technology concentrates the power of the sun’s rays to heat water to create steam which can be used as a sustainable energy solution in industrial processes.

As part of a Knowledge Transfer Partnership (KTP) researchers based at Lark Energy and Cranfield University are exploring the possibilities of the new technology. The results of their research will be submitted to peer-reviewed academic journals for publication later this year.

KTPs enable businesses to improve their productivity and competitiveness through government-funded partnerships with colleges and universities. A KTP is a three way partnership between the business, an academic institution and a recent graduate. The recent graduate is employed at the business and brings new skills and knowledge.

The academic institution benefits by having involvement in research projects and the publication of research papers. The business gains access to academic expertise that it wouldn’t normally have in-house.

Dr Christopher Sansom, Associate Professor in Concentrating Solar Power (CSP) at Cranfield University, said: “An Innovate UK funded KTP is an excellent opportunity for an academic institution and a company to not only solve current technology problems but also to innovate and explore new opportunities of mutual interest.

“As a result of our KTP Cranfield University and Lark Energy continue to collaborate on solar steam for industrial process heat, water treatment, and desalination applications world-wide”.

The Lark Energy/Cranfield University KTP research is looking in part into the potential for energy companies to increase renewable heat input and reduce energy costs. For example, industrial facilities that use fossil fuels to provide the thermal energy required for their processes can instead install the Larkfleet solar steam collector to generate low carbon heat.

Lark Energy’s solar steam system works by focussing the sun’s rays through a Fresnel lens array onto a tube which contains water. The water is heated to create steam which can be used in industrial process heating and cooling applications.

The angle of the lens array can be adjusted through a vertical axis to track the sun and is seated on a circular track which allows the array also to follow the sun’s progress horizontally across the sky. By tracking in both planes, the system maintains maximum levels of solar radiation concentrated on the tubes.

Simone Perini, Cranfield KTP graduate and renewable energy development engineer at Lark Energy, said: “Solar steam builds on existing ideas about using solar radiation to generate heat and takes them a step further.

“Our research is looking into how solar steam can have a positive impact on the generation of sustainable and renewable heat.”

The solar steam array can be also used in desalination, the process of removing salt from water to make it potable. This is of particular value in coastal countries with water shortages.

The two main methods of desalination are reverse osmosis – forcing water through a membrane to collect contaminants – and multistage flash.

The multistage flash method uses heat to convert salt water into fresh water. ‘Flash’ refers to rapidly bringing the water to a boil multiple times or in stages. As the salt water enters each stage of the conversion unit it is subjected to externally supplied steam heat and pressure. During each stage, fresh water vapour forms and is collected.

“Solar steam used in the desalination process will have a lower environmental impact because it is a renewable and sustainable way of delivering the steam needed in the Flash method,” said Simone Perini.