The basic concept of CSP is to use mirrors (heliostats or parabolic troughs) to reflect solar power to a determined target in order to heat up a heat transfer fluid, which directly or indirectly runs a steam turbine and generator to produce electricity. The heat transfer fluid can also be used to ‘charge’ a thermal energy storage system in order to produce electricity when needed (e.g. at night).
The Helio100 system reflects sunlight with heliostats to heat up a receiver. This is designed for a gas turbine at 1000°C, but to avoid burning the receiver, ours is water-cooled for now.
We clearly need to set up some open day due to the big interest. Watch this space.
The Helio100 facility will not initially produce electricity, it will be used as a research and development facility by Stellenbosch University. The heliostat design is intended to go into modular CSP plants from 100 kW and up.
No. The Helio100 technology system is not designed/optimized for a single home and the system needs a fairly large area for installation. Photovoltaic installations currently remain the most appropriate solution for a single home to ‘get off the grid’. While we think our technology is ‘small’, it is true relative to big power plants.
We are getting close, but first read question 7.
There is lots of information available on the academic and research side from the STERG website. Currently we need to protect intellectual property, please check back as the project progresses.
We are always thankful that our projects are interesting to others. If you would like to support the R&D at Stellenbosch University or would like to invest commercially, let us know at helio100@sun.ac.za.
Research is the basis of our technology and the original team comes out of the Solar Thermal Energy Research Group (STERG), please refer to the STERG website.
The technical challenges were not rocket science type challenges which are very complicated. This systems engineering project was tackled rather in a highly complex multidisciplinary and holistic manner. With enough money, anyone can make a heliostat track accurately to hit a point within 1 m accuracy over a distance of 1 km. To do it in a low cost and plonkable way is the trick solved. It did require over 100,000 hours of people time. The non-technical challenges related to those people still more-or-less talking to each other today.
We chose our technical parameters so that this technology is the best right now for small modular next generation CSP but we also chose the parameters to make it the cheapest heliostat for big utility CSP within 5 years from now. The latter does need a bit of time and money.
Absolutely, but to us, small isn’t everyone’s small. A single unit with a 100 kW turbine will need a small village to consume its power.
Our technology is a component of a next-gen CSP technology. There are certainly dozens of other heliostat systems out there, but none are done quite the way we conceived of it.
All solar technologies use roughly the same amount of land. Over time, the amount of land will reduce as technologies get more efficient. Solar panels and CSP concentrators use around a quarter to a fifth of the land surface they stand on and this translates to about 40 m2 per kW of electricity when that electricity is supplied day and night.
Commercial plants based on the Helio100 technology aim for 30 or more years.
The solar field will need ongoing repair over the life in a way that is very different to how traditional power generation works. This will need a blend between automation and labour. A single heliostat is a 2-arm robot and it will need love and care. The power plant is very traditional, but in a turbine sort of traditional, not a diesel generator requiring regular maintenance.
By the time we get to 1 GW of capacity, we expect to comfortably be below R1.30/kWh. If everything goes to plan, we could be below R1.00/kWh. Remember that this electricity is served whenever you want it – it doesn’t only work when the sun shines.