Green, greener, Kalwa

Is it possible to modernize an industrial site that is more than 50 years old in line with the latest sustainability requirements? "Yes", says Siemens Real Estate and delivers impressive proof in India. With steps like an elaborate waste system that includes its own recycling section, a location-wide compression-air system, a central drinking water purification unit and Siemens’ largest solar power system on the roof, Kalwa near Mumbai has become a green showcase for Siemens.

Siemens and India

It’s hard to think of any other country that has such a long-standing shared history with the company. Siemens established itself in India 150 years ago with the construction of the London - Calcutta telegraph line, and its production presence in India dates back to 1956. The company began manufacturing electric motors in Kalwa in 1966, and the location has grown continuously ever since.

The world's largest solar installation on an existing Siemens factory roof

So let's start at the top – with the roofs. India has more than its fair share of sunshine, so it makes sense to utilize natural daylight to the full in the production buildings, thereby minimizing the need for artificial lighting. That's why, right back when the site was originally developed, the decision was made to equip all buildings with so-called "northern lights" – north-facing skylights on the roofs. These allow light to enter the buildings while keeping out much of the heat from the sun. The wired glass used in them has now been replaced with lightweight, more efficient polycarbonate panels. Because up to 60 percent more light can pass through them, they significantly reduce or even eliminate the need for electrical lighting in the buildings. This saves electricity.


A major step toward sustainability is the conversion of three complete building roofs into a gigantic solar installation. Around 6,000 panels with a total area of 12,500 square meters have now been installed on the roofs in Kalwa. This solar installation has a total output of 2 MW, as much as the normal electricity consumption of 2,900 households in India. What's more, it’s the world's largest Siemens project of its kind. A further project is currently under preparation in South Africa. The installation in Kalwa covers approximately 25 percent of the production location's entire electricity consumption, and cuts annual CO2 emissions by 2,400 tonnes – which in turn equates to 62,000 newly planted trees.

Fresh water, trees and e-mobility

Speaking of trees: visually, too, Kalwa is a green location in the truest sense. Over 1,200 trees, measuring more than five meters in height, are on the grounds, all of them registered and cataloged for ease of nurture and maintenance. The 86 species include not only the familiar Mango and the Son-Mohar and Nilgiri trees which are widespread in the region, but also threatened species such as Ashoka, Khaya and Mahogany.


The location is "green" in the wider sense, too – as visitors can witness for themselves when they are picked up from reception in one of the new electric cars and driven to their destination, observing the security personnel riding around on bicycles as they go. Two small measures – but worthwhile contributions to the sustainability account.


But back to the "big" changes. Anyone in India knows that it's never a good idea to drink untreated tap water. At the Kalwa location, however, it's not just possible – it's positively encouraged. Drinking water dispensers from which workers can help themselves to fresh water are provided in all buildings. The fresh water for these is taken from the public supply network, turned into drinking water in the location's own treatment plant, and distributed to 50 drinking water dispensers along a new pipeline measuring more than 1.5 kilometers in length. This measure alone saves around two million of single-use plastic bottles each year.


Anyone marveling at the generous landscaping in Kalwa and its watering system can be assured that no water is wasted here – only treated industrial water is used. The new treatment plant recycles all water on a purely biological basis and enables 97 percent of it to be reused. Some 100,000 liters daily can be used for flushing toilets, cleaning streets and watering the green areas.

Copper, brass and cardboard by the tonne, and less waste

And it's not just water that gets recycled in Kalwa. At the waste segregation depot, employees separate waste into 45 different sorts. Alongside 31 tonnes of copper, 25 tonnes of brass and 350 tonnes of cardboard a year, they also process plastics, electrical components, e-waste, PCBs and aluminum. Once separated, the waste is ready to be reprocessed with authorized recyclers.


Materials as well as temporary stored products and components need to be protected against rain in the annual monsoon season. Previously, this was achieved by setting up protective covers made of bamboo canes with plastic sheeting every year, which would then be torn down and disposed at the end of the season. Here, too, Siemens Real Estate has now developed a long-term solution. The new monsoon shelters, comprising fixed supports covered with a vinyl roof, have a long life and can be erected without major construction processes. They eliminate the need to dispose of temporary materials each year.

New lines for greater efficiency

The measures that you can't see but which make a real difference include the endless kilometers of new lines. The 30-year-old system of electric power lines has been completely replaced and equipped with modern and efficient low-voltage and medium-voltage components – improving the availability of the entire power grid on the campus and extending the service life of the consumers connected to it.


A new, central compressed air supply has also been installed for the entire site. Instead of distributed compressed air stations, the entire production facility is supplied via lines from a central compressed air system which is highly efficient thanks to Siemens technology. This new air-cooled compressed air supply alone saves more than 200,000 kWh of electricity and cuts consumption of cooling water by more than 1 million liters annually.


Some of the buildings – such as the logistics facility, for example – don't need to have air conditioning operating around the clock. In the past, countless small fans were nevertheless mounted on the walls to make the hot summer days bearable. These have now been replaced by just a few colossal ceiling fans which, with a diameter of eight meters, are more reminiscent of a helicopter rotor. They save more than 30,000 kWh annually: equivalent to the electricity consumption of almost ten families of four in Western Europe.

Fit for today and for the future

All in all, the measures implemented make Kalwa a shining example of sustainability. But it doesn't stop there. Further measures are initiated and planned to ensure that this Indian location, so rich in tradition, is also fit for the future; for example the implementation of end-to-end digitalization across the compound. In future, Kalwa aims to be not only a shining example of sustainability but also a showcase for Siemens digitalization. Siemens and Kalwa have a long, successful history, a sustainable present, and a digital future.