Table 1.

Definitions of Green energy and Circular economy.

	Author's	Definition
	Vijay Laxmi Kalyani, Manisha Kumari Dudy and Shikha Pareek	"Green energy reflects the idea about generation of energy from natural resources like sunlight, wind, rain, tides, plant, algae, geothermal heat, etc. having no or less impact on the environment and can be renewed".
Green Energy	Hong Lina and XujunZhai	"Green Energy (GE) as a new concept of energy generation promotes the maximum reuse/recycling of natural resources like sunlight, wind, rain etc".
	ViktoriiaBrazovskaia and Svetlana Gutman	"Green energy entails cutting back on harmful emissions into the atmosphere and improving energy efficiency from current energy systems".
Circular Economy	Ghisellini, Ripa and Ulgiati	“Circular economy (CE) as a new model of economic development promotes the maximum reuse/recycling of materials, goods and components in order to decrease waste generation to the largest possible extent. It aims to innovate the entire chain of production, consumption, distribution and recovery of materials and energy according to a cradle to cradle vision”.
	Geissdoerfer et al. (2017)	“A regenerative system in which resource input and waste, emission, and energy leakage are minimized by slowing, closing, and narrowing material and energy loops. This can be achieved through long-lasting design, maintenance, repair, reuse, remanufacturing, refurbishing, and recycling ".
	Kirchherr et al., 2017	"An economic system that replaces the ‘end-of-life’ concept with reducing, alternatively reusing, recycling and recovering materials in production/distribution and consumption processes. It operates at the micro level (products, companies, consumers), meso level (ecoindustrial parks) and macro level (city, region, nation and beyond), with the aim to accomplish sustainable development, thus simultaneously creating environmental quality, economicprosperity and social equity, to the benefit of current and future generations. It is enabled by novel business models and responsible Consumer".
	Korhonen, Honkasalo and Seppälä	“Circular economy is an economy constructed from societal production consumption systems that maximizes the service produced from the linear nature-societynature material and energy throughput flow. This is done by using cyclical materials flows, renewable energy sources and cascading1-type energy flows. Successful circular economy contributes to all the three dimensions of sustainable development. Circular economy limits the throughput flow to a level that nature tolerates and utilises ecosystem cycles in economic cycles by respecting their natural reproduction rates”
	Ellen MacArthur Foundation	“A circular economy is based on the principles of designing out waste and pollution, keeping products and materials in use, and regenerating natural systems".