Solar thermal solutions for space heating in Ladakh

April 2013 – December 2015

Project area:
Ladakh province

GIZ, MNRE, BMU, LREDA (Leh) and KREDA (Kargil).

Contribution from BMU: Euro 1.1 million
Contribution from MNRE: – to be decided –
Contribution from other partners: – to be decided –

The extreme living conditions for about 270,000 residents in the province Ladakh are marked by cold and arid alpine climate, and the population is exposed for more than 7 month of the year to sub-zero temperatures. It also witnesses scant but irregular rainfall and therefore the availability of biomass is seriously limited. Dried cow dung and sporadically available shrubs are the only energy sources in the area.
Fossil fuels, such as coal, LPG (liquefied petroleum gas) or petroleum are very expensive in this region as they have to be transported from the lowland/plains over the Himalaya. There are only two approach roads that are accessible for only 6 month in a year. Because of the low oxygen content in the atmosphere at altitudes higher than 3000 meters, the energy efficiency of combustion is low, and their transportation creates overloading of the few existing roads and the known environmentally damaging emissions.
The government/administration buildings and hospitals are the only heated buildings, and the residents use crude heating devices such as Bukharis or kerosene/wood stoves to heat the homes in extreme winter season. The consumption of energy for heating in buildings is increasing significantly every year, the demand being further being pushed because of the increasing number of tourists, which incidentally also represent the main source of income.

In this given situation, availability of efficient and locally available heating systems will have competitive advantage. Installing solar thermal systems offers a high saving potential of fossil fuels, which has been hardly used so far in this region. The ongoing efforts of the local NGOs and other local institutions in popularizing the use of solar water and space heating for buildings. Concepts like ‘Trombe wall’ need to be augmented by the additional measures which forms the rationale for this project.
Based on technologies for solar heating of buildings developed by the Solar Institute, Jülich (Germany) for the Argentinean Altiplano region during the last 15 years, the knowledge gained on reliable, economical and locally manufacturable solar systems for solar space heating and drinking water heating shall be transferred to Ladakh. Similarities in climate and social structure of the two regions (Altiplano and Ladakh) make it possible that the technology can be implemented successfully in Ladakh as well.

Main purpose of the project is to adapt and disseminate the solar heating concepts and technology of the high altitude region of Ladakh offering sustainable solutions for energy demand in Ladakh and similar cold climatic regions for heating of buildings.
Pilot installations of solar heating and hot water systems shall be carried out, along with the analysis and implementation of measures to improve the thermal energy efficiency of the buildings. These measures shall be implemented in selected buildings. After a successful implementation and testing of the pilot system, a strategy for large-scale up-scaling of the technology in Ladakh will be developed involving the government, the financial sector as well as local solar entrepreneurs.
Potential for further dissemination of the tested technologies to other areas of Himalaya shall be investigated and analysed in the final phase of the project.

Project Outline and Scope:
The benefits of solar space heating are further enhanced by cost-effective heat protection of the houses thereby improving the efficiency of the buildings. Local construction of the system components (collector, storage…) and their implementation is an important part of the project to assure creation of employment and sustainable development of local markets. Local handicraftsman, engineers and architects will work together with the solar and energy experts during the entire project period of three years to reach these goals. Practical and theoretical workshops and training with special technical and analytical equipment are also part of the process.

Materials for production of solar system components can only be transported to Leh overland after wintertime in May/June, when roads are accessible. That is why the timetable provides the (series-) production of the space heating systems and the implementation of the protection measures during the summer months, when materials are locally available.
During the winter months monitoring of the performance, interpretation and documentation of the logged data, and preparation for the next production- dissemination- and training- phase would take place. After the adaptation of the high altitude solar heating concept to the local conditions, four solar thermal systems will be implemented (two with heat protection, two without for comparison). Heat protection measures will be selected for testing with input from social and economic studies. Based on the first winter experience, improvement and validation takes place. Six further model installations will be performed partially by the handicraftsman alone in the second year. The work will be accompanied by the foreign experts as well as by local institutions to assure the quality of the installations.
A market study will evaluate the possibilities to spread the new technology in Ladakh as well as in neighbouring provinces. Policy documents for marketing/ subsidies and user contribution (different categories) will be prepared for the third year. After the experiences of the second winter, series production of the heating systems will start, accompanied by final protocols for the heat protection of buildings, publicity, and dissemination of information on financing program and subsidies.

Exemplary scheme of heating system:
In the Altiplano a typical system was designed for regions at high altitudes with high solar radiation and low ambient temperatures, with financial support by BMZ (Federal German Ministry for Development Cooperation), in which 30 classrooms, Kindergarten and meeting halls in remote mountain locations have been equipped with this technology. The main considerations in developing this concept were: robust technology, low cost and easy maintenance.
As air is used as the heat transfer medium, typical problems of water-based systems related to freezing temperatures and leakage can successfully be avoided. The low thermal capacity of air enables the system to have low response time so that the heating effect is ready for use soon after sunrise. Optional rock bed storage along the wall or below the ground floor serves as thermal storage for the night time. A small air/water heat exchanger can also be easily integrated to prepare hot water for sanitary use. The flexibility of the design allows adaptation to nearly all existing houses. Positive operational experience over the last 15 years has proven the suitability of this concept which, together with the similar climatic and cultural conditions in Ladakh, forms the
basis of the project proposal.



Institutional Arrangements
GIZ is the lead implementer of the project jointly with the Ministry of New and Renewable Energy (MNRE), Government of India. Implementation partners at the state level would be the state level agencies in Leh (LREDA) and Kargil (KREDA). International and national experts would be engaged as and when required for specific tasks, in addition to developing working arrangements with local NGOs particularly LeDEG which has significant local experience in implementing solar projects for many years. GIZ and MNRE will constitute a Project Monitoring Committee involving officials from GIZ, MNRE and the state agencies.


  • The project has been commissioned through BMU to GIZ in September 2013
  • The of full legal framework (Stakeholder MOU, amendment of ComSolar Implementation Agreement, final contract with local NGO, etc.) is in final stage
  • Two first pilot houses in Ladakh have been completed
  • Several measurement devices inside and outside the pilot houses have been installed and data from first winter season is collected.


Gallery photos