Biomass can be classified as dry biomass (such as wood) or wet biomass sources such as the organic fraction of household waste, agroindustrial waste, sewage and wastewater. Thermal conversion or gasification of dry biomass generates energy. Figure 3 summarizes an approximate level of energy consumption worldwide. Nearly 2 billion kilograms of biomass are burned every day in developing countries. Especially in India, 90% of primary energy consumption is represented by biomass in rural areas (wood-56%; crop residues-16%; dung-21%). Combustion of these sources leads to high concentrations of respirable particulates, gases including CO, SO2, nitrogen oxides and toxic compounds such as benzene and formaldehyde [23]. Wet biomass is less suitable for thermal conversion. These are biotechnological processes in which reactions are catalyzed by microorganisms in an aqueous environment at low temperature and pressure. Aquatic biomass presents easy adaptability to growth in different conditions and has better CO2 fixation accompanied by low nitrous oxide release. Some microalgal biomass is considered a better alternative renewable energy source, terrestrial or aquatic (Botryococcus braunii) (Fig. 1m). In view of the oil content of many microalgae (Table 2), energy recovery from biomass can be easily implemented on a large scale. The photosynthetic efficiency of aquatic biomass is much higher (6-8%) than that of its terrestrial counterpart (1.8-2.2%) [13]. Furthermore, aquatic biomass presents easy adaptability to growth in different conditions in both freshwater and marine water or in a wide pH range. This makes aquatic biomass more adaptive or better CO2 fixation to enable high biomass production. The only viable methods for large-scale production of microalgae are tubular photobioreactors [19] and open-channel ponds [20]. Extensive studies have been conducted for the cultivation of different marine microalgae using a variety of cultivation systems including open ponds and various types of closed photobioreactors [21, 22]. Since several articles already dealt with large-scale production, this article did not focus on these topics. Biomass for energy production has been recognized as an important component of India's renewable energy agenda and this is reflected in the priority given to it by the MNES. There are niches with substantial potential for the use of biomass for energy production, for example bagasse cogeneration in sugar mills, gasifier-based decentralized diesel cogeneration systems in southern India, and biomass waste from agricultural or agro-industries in concentrated geographic pockets [23]. An additional 115 MW of biomass/cogeneration electricity capacity was created in the country in six states during the year, reaching a cumulative power generation capacity of 727 MW.