Chennai startup develops power-saver device for solar units

New Delhi: In a significant development that could give a big boost to the adoption of solar energy in power-starved countries like India, a Chennai-based startup has come out with a unique device - a dual mode micro-inverter.

Kripya Technologies, a Chennai-based company established by Dr V.G. Veeraraghavan in 2010, inspired by the 11th president of India late Dr A.P.J. Abdul Kalam, has come out with the cost-saving inverter that functions in on-grid as well as off-grid modes.

“A significant fall in the cost of photovoltaic solar panels has made solar energy a very competitive and viable alternative to fossil fuel-based generators. Despite this, solar energy adoption in developing countries like India has remained puzzlingly low," said Veeraraghavan, a US-based industry veteran with over 40 years of technology management expertise.

"At Kripya, therefore, we examined the factors that will help increase adoption of solar energy by everyone irrespective of their geographic location and economic status and designed the dual mode micro inverter,” he said.

Typically, an inverter is used to convert the DC power generated by the solar panel into readily usable AC power. The inverters currently available in the market are all designed to function solely, either using power supplied by the grid or expensive battery in off-grid mode, requiring two different sets of devices.

Focusing on solar power units such as rooftop installations, the Kripya team realised that the grid-connected inverters have to depend on the vagaries of power supply as a necessary input for the conversion of DC to AC, while the off-grid inverters rely on very expensive battery storage for storing the electricity prior to conversion to AC. 

These are serious limitations for the adoption of solar energy in developing countries like India where the grid power is not always available -- and even when it is available, the reliability of grid power is low, Veeraraghavan said. 

In addition, the team also recognised that conventional string inverters -- connected to a group of solar panels -- are not optimal for capacities less than 10 KVA for homes and small offices, due to lower efficiency and perennial load shedding that plagues many cities and towns.

The Kripya team thus conceived and developed the Dual Mode Micro-inverter to resolve these issues and facilitate easy adoption of distributed solar energy generation in developing countries. 

Micro-inverters offer the added advantages of modularity, scalability, maximum power efficiency, real time optimisation and superior means for monitoring and control of the overall system. 

Kripya has already filed for patent for the dual mode inverter which is easy to install and use in a plug-and-play mode with minimal or no wiring required. 

The inverter can dynamically detect and switch modes based on the availability of grid power.

As the available solar radiation and associated photovoltaic energy can change even during the day, Kripya has also developed a micro-processor- based load manager which works in conjunction with the Dual Mode Micro-inverter. The load manager has a feature to segment the loads and assign a different priority to the different load circuits of the solar energy system

During operation, the load manager will automatically manage the segmented load circuits connected to the solar energy system and turn off the non-critical circuits while maintaining the critical circuits on when the available harvested solar energy is less than what is needed for supporting all the circuits.

“Kripya is very proud to have developed the products that offer cost effective means for adoption of solar energy by combining innovation, social and environmental consciousness,” Veeraraghavan said.