Skip to main content

Tell us Rohit Ranjan

Rohit Ranjan, an Energy Research Engineer at the Himalayan Institute of Alternatives, Lakdah (HIAL), worked at the Institute for Sustainability and Energy in Construction FHNW from early September to mid-November, where he conducted research with the help of the Institute's experts as part of an international research project to simulate the thermal performance of passively solar heated buildings and help understand and improve the design of such buildings for HIAL and the people of Ladakh. Tell us about it...

«Hi, I'm Rohit. I'm 30 years young and I'm from India - specifically, the northernmost part of India called Ladakh, which means "the land of high passes." Ladakh is located beyond the Himalayas and has a starting altitude of about 3000 m above sea level.

I grew up on the foothills of the lower Himalayas in West Bengal, near Darjeeling, the town famous for its tea. I attended school there and later moved out to pursue higher education.

Already towards the end of my Bachelor of Technology in Aeronautical Engineering in Ajmer (an oasis in the desert state of Rajasthan), I realized that I would do better in renewable energy studies. So I decided to pursue a Master of Technology in Renewable Energy Engineering and Management at TERI School of Advanced Studies in Delhi. This field fascinated and interested me. And it got even more interesting when I got the chance to go to Ladakh at the beginning of 2018.

TERI School of Advanced Studies (Master of Technology in Renewable Energy Engineering and Management)

TERI School of Advanced Studies (Master of Technology in Renewable Energy Engineering and Management)

In Ladakh, I first worked as a volunteer or part-time staff member for SECMOL (Students' Educational Movement of Ladakh), a non-governmental organization that has revolutionized education in the region and is a center for developing ingenious, technically simple but effective solutions to local problems. And there is no shortage of problems here, as temperatures in Ladakh range from +35 °C in summer to -35 °C in winter.

One of the biggest challenges in Ladakh is the need for space heating. Although this need could be met simply by using the sun's rays passively to heat buildings (Passive Solar Heating of Buildings).Using solar photovoltaic systems with an efficiency of 15% to generate electricity and then using the generated energy to generate heat is not very efficient when you have the possibility to trap the heat directly in the building through its design and construction method - and Ladakh has a lot of sunlight; more than 300 sunny days per year. I was therefore interested in,

why the people and government in Ladakh are not using this technology, even though it has been around for 40 years and there have been several successful demonstration projects. What needs to be done to establish it? This is what I have been working on since 2019 working full-time with the Himalayan Institute of Alternatives, Lakdah (HIAL).

Prototyp eines assiv-solargeheizten Gebäudes auf dem Campus

Prototype of a passive-solar heated building on campus. The Himalayan Institute of Alternatives, Lakdah (HIAL), which aims to break the boundaries of conventional thinking and promote learning through the practical application of knowledge.

The HIAL opened in 2017 after Sonam Wangchuk received the Rolex Prize for Entrepreneurship in 2016. He was honored for his invention of the ice stupa, an artificially created ice cone that stores meltwater to reduce water shortages in the Himalayan region. Mr Wangchuk used the money he won as seed money to establish a university for the mountain region, the HIAL. Its goal is to make higher education more experiential and use it to solve problems in the region with its unique challenges.


An ice stupa is a man-made ice cone that stores water - a helpful invention for the Himalayan region where water is scarce.

While my project proposal on Passive Solar Houses PSH was being finalized and I was looking for possible partners and funders for it, Karen Schrader from the Hochschule für Technik FHNW came to Ladakh to meet our founding Executive Director, Gitanjali JB. Karen Schrader had heard about HIAL and the Ice Stupas because one of her students in the Energy and Environmental Engineering program was working on developing nozzles for the Ice Stupa sprinklers and she was an English communications coach who reviewed the report. We met by chance and when I told her about this PSH project, her interest was piqued. A lively exchange by email ensued resulting in the SDC (Swiss Agency for Development and Cooperation) approving the project "Mainstreaming Passive Solar Heating in Northernmost India" or, as we affectionately call it, the "Ladakh Passive Solar Heating (LPSH) Project" on July 1, 2020, which Karen Schrader is managing.

Karen Schrader.jpg

Karen Schrader from the FHNW School of Engineering met Rohit in Lakdah and initiated the collaboration.

The Institute for Sustainability and Energy in Construction FHNW (INEB) is also involved in the LPSH project to provide technical support to HIAL - or me. On the one hand, thermal building simulations are to be used to compare the comfort of a model with the various HIAL constructions, and on the other hand, HIAL is to be supported with the construction and implementation of detailed monitoring in two HIAL buildings. The INEB also introduced me to the topic of thermal building simulation so that I can perform such calculations myself in the future for the further development of PSH.

Rohit_Monika Hall.JPG

Working together on the simulation model, here with Monika Hall from INEB.

In connection with the LPSH project, a student project on PSH in Ladakh was also worked on in spring semester '21 by students in the 4th semester of the Energy and Environmental Engineering program. They used a thermal building simulation to contrast the comfort of a PSH and non PSH and looked at the economics of PSH/non PSH. The basis was a HIAL building where the PSH construction was replaced with a standard Indian construction. Karen Schrader and Monika Hall coached this project, in which I was also involved to learn about the structure of an EUT student project. In addition, I had the chance to be introduced to project management by Yvonne Zickermann (HT), as it is envisaged that HIAL will also offer such projects to students. However, due to Corona in the spring, everything had to take place online. I was therefore particularly pleased that I was able to meet three of the project members in person during my stay at FHNW.

P4 Team EUT.jpg

The exchange with the students of the "Analysis of HIAL passive solar heated houses" project in the study program Energy and Environmental Technology EUT was not neglected either: Rohit with Dominic Gassl, Sneka Sugumaran and Gian Huser (from left to right) Anthea Nauer is missing.

During the two months in Switzerland, I was able to learn a lot, especially about the simulation model and how it can be used to develop replicable designs, which will help to understand and improve the design of such buildings for HIAL and the people of Ladakh. That is one goal of this international research project. All in all, it was incredibly exciting and the collaboration was a lot of fun. Everyone has been very welcoming and exceptionally generous, friendly and fun. It has been great here!»


Rohit in the Cube at FHNW Campus Muttenz.