Interview by Rikki Stancich

Founded in 2007, HelioFocus has developed a full system solution for generating solar power using air as the heat transfer fluid.

The company’s product comprises a unique volumetric receiver positioned at the focal point of a large parabolic dish, onto which concentrated sunlight is reflected. The receiver converts the sunlight into high temperature  air, which can be used for a variety of applications.

The company’s primary focus is to provide solar-booster technology to augment existing power plant capacity. HelioFocus is additionally developing solutions for standalone power station and distributed power generation & CHP, which it intends to implement in the near future.

The company’s major shareholders are IC Green Energy (Israel) and Zhejiang Sanhua (China).

CSP Today:  HelioFocus has developed the 'parabolic dish', a dual-axis dish comprised of parabolic mirrors arranged on a Fresnel configuration to deliver the highest possible optical efficiency. Can you briefly explain how it works?

HelioFocus: The HelioBooster operates at high efficiency scales and runs at low operational costs. The product comprises of a field of large parabolic dish concentrators (500 sq.m. per dish) that harness temperatures up to 650°C.

Each dish channels the sun radiation onto a proprietary volumetric receiver, which generates high temperature air. The air is then transferred to a central heat exchanger that generates high temperature steam. The steam is delivered to the main steam stream of the power plant turbine, generating clean electricity.

CSP Today: According to Heliofocus, the parabolic dish concept yields a significant reduction in the system cost. How is this achieved?

HelioFocus: When referring to costs, one should understand the industry's most important parameter - Levelized cost of electricity (LCOE). This means how much it cost to generate 1 kWh of electricity. LCOE is driven directly from CAPEX (capital equipment installation costs) and OPEX (operational and maintenance costs).

HelioFocus addressed these two segments. In the installed costs, we have managed to dramatically reduce the $/installed capacity (i.e. solar field size needed for a kWh/annual production requirement) and the O&M costs (i.e. amount of water used to clean mirrors).

In addition, HelioFocus tracks the sun in two axes, harnessing the sun in a 1:2000 concentration ratio. This contributes significantly to cost reduction, as it enables us to produce more kWh than any other CSP technology, as well as to work at higher thermal efficiencies since we outperform the HTF (which is air) temperatures.

CSP Today: At what scale are HelioFocus’ solutions available? What is the output of the dish at these respective sizes?

HelioFocus: The commercially available solution is a boosting application. The HelioBooster connects to existing power plants (combined cycle or coal) and increases the overall annual electricity production of the plants by adding solar steam.

HelioFocus’ future products include a stand-alone application, which will provide a cost-effective solution for producing solar electricity to the grid at minimum capacity of 50MW; a CHP application (cooling, heating and power); and a distributed solution that can support smaller scale usage. HelioFocus aims for the utility scale and national infrastructure; therefore no application will be used for rooftops or domestic usage.

CSP Today: HelioFocus has developed an application for utility-scale electricity generation, called the e-Dish, which incorporates a steam turbine. How does this solution work?

HelioFocus: The e-Dish is a code name for direct electricity generation product. The company has 3 different products within this category but the principle is simple: imagine a solar field of a single to hundreds of dishes that generates high temperature air (up to 950c) or high temperature steam (i.e. 540c) as heat transfer fluid (HTF).

This HTF feeds an off-the-shelf turbine, which generates electricity. This application is important for local power distribution in areas that have good solar radiation, yet lack sufficient grid infrastructure.

We have already successfully demonstrated a small-scale application within this family by using a micro turbine with a single dish to generate 65kWe and feed the grid.

CSP Today:  HelioFocus also offers an ISCC solution, the HelioBooster. How does it compete with other CSP technologies on resource requirement (land, water, etc), ease of integration, and cost?

HelioFocus: Regarding land usage, once you are working at high concentration ratio and tracking the sun on two axes, you can achieve the same kWh output on an annual basis from a smaller footprint. We have successfully demonstrated this in China, where we achieved a footprint difference up to 2.5 times smaller than other CSP technologies.

Water usage is driven directly from that – not only does HelioFocus’ technology consume less water, given that it requires water only for mirror cleaning; our solar field is now even smaller.

As for ease of integration, once you are able to work at high temperatures your flexibility increases significantly. For example, it enables a more convenient way to hook up with the utilities using high pressure / low pressure ducting, rather than using turbine extractions (directly due to our high temperature advantage). High temperature is critical for simplifying the process.

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

Rikki Stancich: rstancich@csptoday.com