Interview with CBE awardee Prof Ravi Silva

By Sajitha Prematunge

Every hour the Earth’s atmosphere receives enough solar radiation to meet electricity needs of every human being on Earth for a year. Consequently, the world’s greatest problem can be fixed with just one percent of solar radiation the earth receives. The catch? It’s exorbitant. Fulfilling energy needs has remained an insurmountable challenge for centuries as this huge influx of solar energy is wasted for want of a cost effective way of harnessing solar energy, at least until researchers, the likes of Prof Ravi Silva can fix it. Imagine a technology that would enable printing of solar cells using a process similar to that of printing a newspaper. It would enable production of square kilometres of organic solar cells at a fraction of the current cost, theoretically. This is the kind of cutting-edge technology Silva and his ilk are involved in. Following is an exclusive interview with recent CBE awardee Prof Ravi Silva.

UK-based scientist of Sri Lankan origin and Surrey University Advanced Technology Institute (ATI) Director, Professor Ravi Silva was recently awarded a CBE or Commander of the Order of the British Empire, one of the highest ranking Orders of the British Empire award, for his services to Science, Education and Research over the last three decades.

Silva joined the Cambridge University Engineering Department for his undergraduate and postgraduate work, immediately after his secondary education in Sri Lanka. He joined Surrey in 1995. He was one of the key investigators for the £10m ATI, established in 2002 with the hopes of bringing all solid state electronics and photonics research at Surrey into a dedicated institute. Silva has been its director of since 2005 and also heads the Nano-Electronics Centre (NEC), an interdisciplinary research activity. He helped set up one of the largest carbon nanotechnology laboratories at Surrey.

In 2013 he was elected a Distinguished Professor at Chonbuk National University and in 2016 a Visiting Professorship at Dalian Technology University, China. In April 2017 he was appointed Honarary Director to the Zengzhou Materials Genome Institute (ZMGI), China. In March 2018, he was elected joint Editor-in-Chief of Wiley’s Energy and Environmental Materials. More recently, he has set up the £4m industry-academia Nano-Manufacturing Centre and in 2019 the £1m Marcus Lee Printable Solar Cell Facility.

His research has resulted in over 620 presentations at international conferences, and over 600 journal papers, with circa 21,000 citations and won grants of over £30m over the last two decades. In 2002 he was awarded the Charles Vernon Boys Medal by the Institute of Physics, and in 2003 the IEE Achievement Award. The same year he was awarded the Albert Einstein Silver Medal and Javed Husain Prize by UNESCO for contributions to electronic devices. In 2003 the largest EPSRC Portfolio of £6.68M was awarded to Silva and his team on Integrated Electronics which examined nanoscale design features on the optical and photonic device properties. In 2004, SRIF award for £4M, to set up a Nano-Electronics Centre for multidisciplinary research, was awarded to Silva.

He was awarded the Royal Society Clifford Patterson Award for 2011. In 2014, he was awarded a premium medal by the Institute of Engineering and Technology (IET), the JJ Thompson Medal for contributions to Electrical and Electronic Engineering. In 2015, he won the Institute of Materials, Minerals & Mining (IOM3) premium award, the Platinum Medal for contributing to materials science, technology and industry. In 2016 he won the Government of Sri Lanka Presidential Award in recognition for many contributions in the field of nanotechnology.

Since 2005 he has worked with the National Science Foundation (NSF), Sri Lanka to develop nanotechnology as a vehicle to generate wealth and alleviate poverty in the country. Silva was on the advisory board of Imprimatur Ltd and the National Nanotechnology Initiative (NNI) of Sri Lanka. He was an Advisor to the Minister of Science and Technology in Sri Lanka, and helped set up the Sri Lanka Institute of NanoTechnology (SLINTec) and the Nano-Science Park NANCO (private) Ltd in 2008. He currently acts as an advisor to both these entities and sits on the director board. He has acted as advisor to many national and international organisations, including US, Korean, Japanese, Chinese, Indian, Sri Lankan, Singaporean, Saudi Arabian, Israeli, Hong Kong, Portuguese, Canadian, Brazilian and European governments.

His research interests encompass a wide range of activities with a focus in nanotechnology and renewables. Other fields of interest include electronic devices, sensors and X-ray detectors. “The area that is most significant at present is how to keep our planet safe for the next generation,” said Silva. He explained that climate change is an existential threat for humans, and we must reduce our carbon emissions. He pointed out that the best route to do so is with replacing fossil fuels with renewable energy. Much of his research at present looks at the fabrication and manufacture of new and cheap solar cells, together with battery storage that can act as an integrated solution to green energy provision.

Q:

Which of your research has been put to best practical use, in your opinion?

A:

There are a number of areas in which research conducted within my group has been put to good use. In the field of electronics, it is very difficult to pinpoint precisely where your devices are used as there are many thousands of devices and inventions in even basic consumer electronic systems. For example, patents from our group have been licensed to companies such as Philips, BAE systems, Airbus, Bombardier, Surrey Nano Systems and Silver Ray and they form components of a bigger system or application. The most obvious example of Nanotechnology developed in the group was in the winter Olympics at PyeongChang where the Hyundai Pavilion was covered with Vanta Black, the blackest man-made material in the world. This was also demonstrated through the paint on the BMW X6 model, ‘VBX6’ at the Frankfurt Motor show. These materials originated from research in my labs at Surrey.

Q: What are the contributions solar energy can make to drive the world to a carbon net zero position?

A:

Solar energy is crucial if the world is to go to a net carbon zero position. Typically, the Earth gets enough energy from the sun in one hour to power the entire population of earth for one year. Therefore, the current 80 percent use of fossil fuels to power the world must be decreased significantly in the next 50 years, to be replaced by green energy. In developed countries such as Germany there are predictions which show solar energy would make up 80 percent of the total energy use in 2100. This is simply due to the overwhelming evidence that points to these sources as the most appropriate green energy provider.

Q: Why are governments reluctant to commit fully to solar power?

A:

At present the cost of solar and the inbuilt infrastructure available for fossil fuels makes governments reluctant to examine other sources. The local energy generation and transmission system will need to be overhauled and new investments made in energy, supply, transmission, storage and distribution.

Q: What can Sri Lanka do to popularise renewable energy?

A:

Sri Lanka’s renewable energy efforts are mostly ad-hoc and requires coherent policy and planning. Education on the advantages of renewable energy and how it can be implemented can help. At present, should a full cost analysis be performed on solar energy, it will come up as the most cost-efficient energy provision available in countries such as Sri Lanka.

Q: How do you manage higher efficiency solar energy technology, while maintaining lower cost?

A:

The cost of solar energy provision has been coming down exponentially. If we take one of the measures to judge the cost of solar electricity, cost per Watt, in 1970 this was an eye watering US$74 per Watt. This dropped to below US$ 10 in 1990 and today this is below US$ 20 cents per Watt. The Obama regime ran the Sun Shot Challenge to push the cost of solar electricity below US$ 1 per Watt, as this was when it became competitive with fossils. We are well below that now, and the cost keeps getting lower. Current 450W solar modules can be obtained highly competitively below US 150 if it is bought in bulk.

Q: Yet you have admitted that energy is one thing that has defied all economic models, including the axiom of Supply and Demand. Why have solar energy expenses kept rising rather than coming down, with technological development?

A:

Adam Smith said supply and demand should dictate cost. In solar there is 10,000 times over supply of energy. The problem is the cost of solar cells. We are looking to reduce this with sprayable solar cells. But even today the cost of solar for large solar farms can be well below 10 cents US$, if the infrastructure is provided for the investment to take place. For example in India large solar farms have been set up with costs as low as US$ 4 cents per kilowatt hour with the number below US$ 2cents in Mexico. There is no reason to believe we cannot have similar low-cost solar electricity in Sri Lanka.

Q: What are energy cost drivers, and do they apply to the World Energy provision and by extension to Sri Lanka?

A:

Ease of production of energy, raw material provision and the infrastructure dictates the final costs. There is no reason to believe we cannot provide the raw materials needed, when this happens to be sun light. Furthermore, with the enviable hill country with hydroelectricity provision we have a ready-made battery to store energy with pumped hydro.

Q: Do you mean hydropower can be used in conjunction as a storage technology, to store solar energy during off peak hours or during the day and discharge it by night?

A:

Absolutely. Nature has blessed Sri Lanka with some wonderful geology to allow for this to be done at scale. The NSF and universities should be looking to build on this to provide the country with the ideal solutions to their energy needs. Pumped hydro can be used to store hydro-energy when there is too much electricity produced by solar energy, so it can be used in the nights. The 40 percent hydro-provision is near ideal to ensure base load needs are met, for the rest of the energy to come from solar and wind. I am also sure there will be large scale battery provisions coming soon, with companies such as Tesla and 8minutes already demonstrating this.

Q: What are smart grids and its benefits?

A:

If renewable energies are to contribute to nations energy provision, they need to be able to interface well with the current energy provision and transmission. In particular for solar and wind-based energy to feed-into the national grid, a robust energy network with smart grid provision will help. Smart grids also allow for smaller local networks to provide renewable energy in an efficient manner, having appropriate interfacing with the on-grid supply and often back-up energy storage provision.

Q: What obstacles delay power generation sectors from adopting smart grids?

A:

The singular obstacle is inertia and sticking to old infrastructure, without looking to plan ahead for future energy provision.

Q:

What are polymer cells or organic photovoltaics, and their benefits.

A: In the future, using polymer technology, we can produce solar cells with 15 percent efficiency at a fraction the cost of silicon solar cells. This is driven primarily by the very much lower material cost, together with the thousand-fold decrease in active materials used to make solar cells. By adding nanoparticles into the polymer solar cells you can improve the efficiency even further and thereby give better energy per cost. Under these circumstances the energy payback time is below six months.

Q: What is carbon electronics? And what are its applications for a developing country like Sri Lanka?

A:

Carbon electronics uses the element C for the fabrication of electronic devices. Nano-carbons such as graphene, carbon nanotubes and polymers are becoming more important on a daily basis to provide solutions in electronics, energy and structural materials.

For Sri Lanka, it can make a huge difference. Particularly when some of the highest quality graphene can be produced with the vein graphite available in the country. This can not only be used for next generation electronic devices, but also for lighting and even electrodes for batteries. Companies such as Ceylon Graphene Ltd. have been established in the Sri Lanka Institute of Nanotechnology (SLINTEC) to provide just this impetus to the national innovation eco-system.

Q: Where does carbon electronics factor in, solar energy generation?

A:

Polymer based carbons, particularly if mixed with nanomaterials can be used for next generation solar cells. Only a fraction of the material needed in Silicon solar cells, to produce high quality modules, is required when polymer based carbons are used as active materials.

Q: What are carbon electronics’ other benefits?

A:

We can also use the nano-carbon materials to make major components of the battery, such as its electrodes. So, not only energy scavenging, carbon electronics can also help in energy storage.

Q: What are the benefits of unlimited energy?

A:

Some say there is a significant correlation between national development and energy use per capita. The worlds most developed countries also have the highest per capita use of energy.

If we had unlimited energy, the world would be a very different place. With unlimited energy we can wipe out the poverty gaps between the nations; there will be enough energy to provide clean water to all using desalination technologies; we can wipe out famine with food crops grown under ideal conditions; we can ensure maximum energy is focussed on new drugs, vaccines and highly nutritious foods.

Q: What is your opinion on research culture in Sri Lanka Universities?

A:

Sri Lanka universities have high quality researchers, but less provision for them to be able to fully exploit their prowess to help the nation or have an enterprise culture to contribute to society. A step change is needed to motivate researchers to help elevate the country’s science and technology base with their efforts. High quality research should also be given fast track promotion within the sector.

Q:

In a technological perspective which areas are viable for expansion and which are not, for a country like Sri Lanka?

A:

Sri Lanka needs to motivate and energise the younger generation to contribute fully to the nation. Training in enterprise and spinouts should be made available with suitable grants for technologists to develop their inventions and products. The eco-system for entrepreneurship should be developed, with the universities taking a lead by example, on how they can value add to Sri Lankan raw materials and technologies. In the fields of nanotechnology, energy, materials, AI and new technologies they have much to offer.