Evacuated Tube Collectors
Because of a comparably lower price, vacuum tube collectors are becoming more and more popular in India. Based on a capacity of 100 litres of warm water per day, an average thermosiphon system with flat plate collectors is sold at INR 20,000 (EUR 208), whereas a solar water heater with a vacuum tube collector costs on average INR 16,000 (EUR 167). To protect the business of the around 60 flat plate collector manufacturers in India, the Ministry of New and Renewable Energy (MNRE) issued a memorandum on 20 October 2011. Its most important sentence says that, “manufacturers shall import no components other than ETCs (Evacuated Tube Collectors)”.
It follows from this memorandum that a thermosiphon system with vacuum tubes as shown on the picture above cannot be imported as a complete set, but only its tubes can find their way to Indian territory – whereas the tank, the mounting system, the piping, etc. have to be manufactured locally. In addition, MNRE will soon release a list of the Chinese vacuum tube suppliers permitted to import their products to India. Only system suppliers which fulfil these requirements can be added to the list of approved solar water heater manufacturers, whose systems can be subsidised by the national grant scheme. So far, it has not been made entirely clear whether companies can import complete vacuum tube collectors with manifolds for large-scale, pumped solar thermal systems.
The memorandum stipulates that products can be picked from the market and have to be verified by an MNRE-appointed committee. In case requirements are not respected, the ministry may apply the penalties laid down in the memorandum, from a first warning to a permanent exclusion from the MNRE list of approved manufacturers.
Several manufacturers welcomed the announcement, as it will result in the systems being sold at benchmark prices. “There were several manufacturers who were importing complete systems of sub-standard quality and selling them at cheaper prices, which unsettled the market and also caused confusion among buyers,” Surendra Kumar, Managing Director of collector manufacturer Nuetech Solar, explains.
Hemant Revankar, Chairman of the Solar Thermal Federation of India (STFI), also hailed the new requirements. He mentions that, “STFI has already laid out strict guidelines for manufacturers who wish to become members and the MNRE guidelines precisely match our criteria”. Revankar also assured full cooperation by STFI for manufacturer inspections.
To make activities on the market more transparent, the memorandum defines two different types of solar water heater manufacturers. Category 1 includes companies which manufacture the hot water storage tank and the mounting system in-house. Category 2 includes companies which purchase the storage tank or mounting system from an OEM manufacturer that has to be an Indian-based company.
The October memorandum was preceded by an MNRE memorandum from 2 September 2011, entitled “Minimum Requirements for Installation of Solar Water Heating Systems in Field” (see attached pdf). The two-page guideline specified requirements for flat plate collectors, vacuum tubes and storage tanks.
Regarding ETCs, the MNRE has now made it mandatory to use tubes with 3 layer coatings on the inner tube. System integrators assure that they will provide all details about which company supplied the components – whether locally purchased or imported. The systems should have a minimum of 1.5 m2 of absorber area for a 100 litre tank capacity. The formula to calculate the absorber area is meters = number of tubes times radius in meters times length in meters.
For the official memorandum from 20 October, see: http://mnre.gov.in/list/list-etc-m.htm