The NWIRES project focuses on the study of novel nanowire based solar cell device structures. The PI of the project Prof. Harri Lipsanen and post-doc researcher Veer Dhaka visited India in February 2015 to meet the collaborators in IIT Delhi and to attend a conference in Chennai. Now, as a first exchange visit of this joint project, the Indian team of researchers is currently visiting Aalto. Interestingly, the visiting Indian PI told us that there is a heat wave going on in northern and southern Indian states, and the temperature topped 47 degrees last week in New Delhi, this is already in May! Our visit to India earlier in February was in many ways eye-opening. For a Finn there were many things different than in here, for instance an enormous number of vehicles in chaotic New Delhi streets. The air quality was extremely bad; even though the sun was shining the sky looked hazy due to the pollution layer as reported in the previous blog of Anders Lindfors.
India is a rapidly developing country, with a population of 1.4 billion; its energy requirements are huge. Currently, 67% of the total electricity production in India is achieved through coal burning power plants, which releases huge amount of harmful carbon emissions in the environment. Coupled with carbon emissions from vehicles and wood burning, the problem is very complex. These gases build up in the environment and trap the heat, resulting in temperature rise. Use of renewable energy, especially solar could be the answer to this problem. Not only in India, all over the world there is a great need to push the solar energy production. Indian government has recognised the use of renewable clean energy and initiated joint research with the European and the US governments.
In that background, this project on energy research with IIT Delhi is of significance. Germany is the world leader in use of solar energy, while the trend of solar energy in India is rising at a great pace (renewables power share in India is currently about 12%, with solar coming in at 3rd place after wind and geothermal). In Finland, solar energy has negligible contribution to the total power generation. So, both countries have a great potential for a joint work on solar energy research. In fact, as we are writing this blog, a group in our department in Aalto University reported record efficiency using nanostructured black silicon solar cells.
In addition, Fortum has recently launched a greenfield solar PV plant in Madhya Pradesh, India. The 10 MW solar plant based on thin film compound semiconductor CdTe cells shall offset more than 18000 tons of CO2 emissions equivalent annually. These are certainly good motivations for our research project on nanowire based solar cells. With compound semiconductor nanowires, the current highest reported conversion efficiency is 13.8%, which is likely to be improved in the near future. Our final goal is to achieve high efficiency using low cost cell structures that employ a minimal consumption of materials.
Text: Harri Lipsanen and Veer Dhaka, Aalto University