Raygen Technology

Introducing PV Ultra

PV Ultra’s next generation technology is a world beater. In 2014, RayGen set a world record of 40.4% efficiency with the University of New South Wales.


RayGen pioneers PV Ultra, an innovative, next generation combination of high-efficiency solar cells and low-cost mirrors.

The PV Ultra system uses a field of active mirrors (known as heliostats), which collect and focus sunlight over 600x to a tower-mounted central receiver. The receiver contains an array of ultra-high efficiency modules which are actively cooled. The modules convert the light into electricity (there is no heat turbine), and captures thermal energy from the cooling as a useful by-product. The mirrors only focus the light onto the receiver, they do not generate electricity.

Least cost solar collection

The heliostats in the ‘collector field’ follow the sun throughout the sky with two-axis tracking as standard. The mirrors are self-powered (with a small on-board solar power panel) and communicate wirelessly with the tower – no field wiring is required.

The mirrors are inexpensive to manufacture, to install, and to maintain. They do not need foundations and are highly error-tolerant. They can be mounted on a driven-pole and only a spanner is required to install and commission.

Highest efficiency solar conversion

The ultra-high efficiency module mounted in the tower is actively cooled and converts the focussed sunlight into electricity as well as heat.

The module uses only the best solar cells available which are twice as efficient as conventional silicon PV cells at converting light to electricity. In addition, the sunlight that is not converted to electricity is captured as heat and available for many applications.

Thus, PV Ultra creates useful commercial products from over 80% of the sunlight that strikes the mirrors – conventional silicon PV typically utilises less than 20% of the sunlight that strikes the panel surface.


Comparison with other solar technologies

RayGen’s PV Ultra combines the best of other solar technologies to deliver the superior product.

Comparison with Silicon PV

The ultra-high efficiency module RayGen uses is nearly twice as efficient when compared to traditional silicon PV panels (up to 40% compared to 20%), the light is focused over 600x by mirrors onto the PV Ultra panel in the receiver. The PV Ultra panel produces over 1200x the electrical power vs regular silicon photovoltaic panels of the same area.

This means that PV Ultra is much more value intensive. Standard photovoltaic systems require 6,000m2 of flat panels per MW. PV Ultra uses 3,600m2 of mirrors and just 4m2 of photovoltaic material per MW. That’s right – every square metre of RayGen modules can produce 250kW of electricity (and that’s before considering over 400kW of heat energy).

Both Silicon PV and PV Ultra systems require the same land area – however the optimised 2-axis tracking field can increase electricity yield by 15% vs standard silicon PV. In addition, the heliostats are wireless and raised off the ground, enabling dual land use, such as grazing.

Because the mirrors and tower are made using existing technology drawn from automotive and electronics manufacturing, a PV Ultra installation can have a far higher level of local content than imported solar panels.

Comparison with Concentrated Solar Power (CSP)

PV Ultra also has clear advantages over Concentrated Solar Power (CSP).

Like CSP, PV Ultra collects the sunlight using heliostats focussing light onto a tower, but that is where the similarities end. Where CSP uses a thermal receiver and complex, expensive heat turbines that require a lot of maintenance, PV Ultra uses a photovoltaic cell that requires little maintenance and upkeep.

To be efficient, CSP requires tall, massive towers over 150m high (similar to a sky-scraper over 50 storeys high).

By contrast, PV Ultra’s tower is thin and less 50m high (similar to a standard light tower). RayGen has already demonstrated its commercial efficiency at 1/4MW.

Comparison with Concentrated Photovoltaic (CPV)

PV Ultra has several advantages over CPV.

All of the high-tech semiconductor components (modules) are all contained in the small factory built ‘receiver’. The collector field is aligned to the receiver with software, not hardware. This means that manual field alignment is not required, software correction allows low precision hardware and low precision installation, and manufacturing tolerances can be higher.

The manufacturing processes for the cell modules and heliostats use existing automation technologies currently used in industry – automotive manufacturing techniques and facilities for the heliostat, and standard electronics manufacturing for the cell modules. This means that PV Ultra delivers reduced cost to scale, equipment is pre-fabricated and installation is rapid, labour costs are lower, and leveraging existing automotive and electronics manufacturing makes it easy to meet local content requirements.

A 1 MW receiver with a dense module array is just 4m2. This allows for easy shipping, upgrades of new modules, centralised heat management system enabling heat sales, centralised power conversion that eliminates field wiring, and optimised flux management that enables constant flux.


Electricity market for PV Ultra

PV Ultra is a purpose-designed system for utility projects and large behind-the-meter C&I customers.

PV Ultra is not a scaled up domestic product. It is ideal for applications in excess of 0.25MW electricity, with co-generation heat potential nearby, in regions with moderate to high solar resource, and with land available for placing mirrors.

2-Axis tracking as standard can increase electricity production by up to 15% more electricity per annum than standard fixed plate PV.

Typical installations include:

  • Utility,
  • Behind-the-meter commercial and industrial customers, and
  • Large community and off-grid projects.

The PV Ultra technology is not suited to rooftop applications.


Heat market for PV Ultra

PV Ultra is a unique co-generation product.

PV Ultra generates heat; heat that can be used to replace existing fossil-fuel heat generation, or to create potable water using multi-effect distillation desalination. The heat sales can be used to offset the costs of the project meaning the PV Ultra system can pay for itself far more quickly than competing solutions, as well as substantially increased carbon reduction.

PV Ultra is the only tower-mounted concentrated PV technology commercially available that offers electricity and heat. The PV Ultra system generates over 7GJ of heat for every 1MWh of electricity.

Co-generation yields higher energy revenue, higher asset utilisation and a wider product range for each solar power plant. The heat can be used to deliver:

  • Reduction in gas, diesel and other heating consumption
  • High quality water, via Multi-Effect Desalination
  • Dispatchable power, via Organic Rankine Cycle and the Kalina Cycle
  • Low cost storage, via improving the round-trip efficiency of Compressed Air Energy Storage

Other advantages

PV Ultra has potential for highest Customer Internal Rate of Return of any solar technology, with multiple additional benefits.

Future-proof

With PV Ultra, your investment is guaranteed, with long-term investment protection and options for future software and module upgrades.

Local manufacturing

Heliostats and mast can be manufactured and/or assembled local to the project.

Lighter footprint

Heliostats do not require field wiring nor foundations. Dual-land use (eg grazing for sheep) as standard.

Highly capital efficient manufacturing

PV Ultra requires just 3,600m2 of mirrors, and 4m2 of modules per MW as opposed to PV’s requirement of 6,000m2 per MW. It is also at least 10 times the capital efficiency of standard silicon PV panels – requiring less than US$50m per 1GW of manufacturing capacity.


Proven Technology

With two commissioned sites and one to be commissioned by Q1 2018, the technology has proven operating performance.

The technology has been deployed in Australia and China:

  • 0.2MW industrial agricultural business in regional Victoria, Australia.
  • 0.5MW expansion of the regional Victorian site, due to finish commissioning in Q1, 2018
  • 0.2MW manufacturing business in semi-urban Zhuozhou, China.

In 2014, RayGen set a world record of 40.4% efficiency during a technology trial with the University of New South Wales.