1.6 Renewable Energy
Renewable Energy
2020-07-06 18:41:23
- continuously replenished, less emission, available locally
- most are non polluting except biomass
- Primary source are renewable energy viz solar, wind etc. Secondary are non-renewable gen through conversion of coal, oil, natural gas
Solar Energy
2 ways to produce is either through
- Photovoltaic cell which have 2 semi conductors np or pn type
- Solar-Thermal electricity which focuses sunlight to heat a surface containing liquid and generating electricity
Solar Energy in India
- states with high solar radiation are RAJ-Guj region, Ladakh, AP, Maha, MP
- National Solar Mission
- IN installed capacity is 54GW (March 2022)
- National Institute of Solar Energy NISE is apex R&D institution in Solar energy field under MNRE.
International Solar Alliance (ISA) #body #important
- was launched at the CoP21 of UNFCC in Paris 2015.
- Treaty based Intergov org for countries that are lying fully or partially between Tropic of Cancer and Tropic of Capricorn. Treaty was signed at Marrakesh, Morocco.
- Secretariat at Gurgaon
- Objective is to drive demand, force prices down, standardise solar tech, to foster R&D.
- 124 countries are mem
- President of ISA Assembly is MNRE minister.
Various Programs launched under this are
- Awards such as Vishvesvaraya, Kalpana Chawala and Diwakar.
- ISA CARES to solarise one primary health care
- ISA Technical fund implemented along w/ ADB
- ISA, India and World Bank tripartite agreement for One Sun, One World and One Grid Initiative.
- Coalition for Sustainable Climate Action was launched comprising of global public and private corporates.
Solutions to problems of various solar related segments.
Luminescent Solar Concentrator (LSC)
- device that uses a thin sheet of material to trap solar radiation over a large area and then directs it to cells mounted on the thin edges of the material layer.
- they are made up of polymethylmethacrylate PMMA and doped with luminescent agents like organic dyes, quantum dots etc.
- used to replace solar cells since it is cheap, effective in clouder climates, can collect and diffuse solar radiation, broad absorption range, long term stability
IRENA International Renewable Energy Agency #body #important
- has 150 member nations with Headquarters in Abu Dhabi
- is an intergovernmental organisation
- promotes all type of renewable energy
Wind Energy
- Total installed capacity of 40GW, 4th largest in World
- Wind farms are either onshore or offshore (more expensive)
- Variables that determine wind electricity gen are speed, blade radius and air density
- 2 types of designs are Horizontal axis design (commonly used) and Vertical
- National Wind Energy Mission was proposed
- MNRE has set target of 60GW by 2022
Hydro Power
- cheapest most cleanest but env issues associated w/ it
- Small hydro : installed capacity of less than 25 MW, 5400 such sites in India
3 Types of Hydropower Facilities:
- Impoundment : uses a dam to store river water in a reservoir
- Diversion : a portion of a river is diverted to low through a turbine, may not require a dam.
- Pumped storage : it acts as a battery, when demand is low it pumps water from lower reservoir to upper and during high demands viceversa
Ocean Thermal Energy
Wave Energy
- is transfer of energy from the wind to the sea.
- first wave energy, project with a capacity of 150MW, has been set up at Vizhinjam near Trivandrum
Tidal Energy
- extracted from tides by creating a reservoir or basin behind a barrage and passing tidal waters through turbines
- major tidal energy project was proposed to be set up in Hanthal Creek in Gulf of Kutchh
Biomass
- derived from carbonaceous human and natural wastes
- #concept Biomass does not add CO2 to the atmosphere as it absorbs the same amt of Carbon while growing as it releases when consume
- In has set target of 10GW by 2022, Total installed capacity is 10GW
- Incentive schemes have been introduced for cultivation of Jatropha
- Central Finance Assistance CFA by MNRE to Biomass projects
Process that Convert Biomass to Useful Products #important
Gassification
- directly burned in the presence of excess air at high temp
- gas produced during gasification is known as producer gas which is a mixture of carbon monoxide (25%), hydrogen and hydrocarbons (15%), and carbon dioxide and nitrogen (60%).
Pyrolysis
- Decomposition of organic matter by heating it in absence of air
- gas given out is called Syngas
- Typically syngas is 30 to 60% carbon monoxide (CO), 25 to 30% hydrogen (H2), 0 to 5% methane (CH4), 5 to 15% carbon dioxide (CO2), also some traces of water vapour and sulphur compounds.
Anaerobic Digestion/ Biomethanation/ Methanogenesis
- is a scientific process whereby microorganisms in an anaerobic environment decompose biodegradable matter and produce rich biogas and effluent
- Hydrolysis, acidogenesis and methanogenesis are 3 process that take place sequentially
Cogeneration
- one type of energy must always be heat and other may be electricity or mechanical energy
- Ex steam generated from boilers of power plants are used to run turbines to produce electricity
- saves cost, primary usage in sugar, rice, mills, distilleries, steel, chemical, cement plants etc
- Bagasse cogeneration states are AP, TN, Ktaka, Maha, UP
Waste to Energy
- potential to divert waste from landfills
- estimated potential of 225MW from all sewage
- total installed capacity is 100MW
Major Constraints
- Tech needs to be imported, cost of setting such projects is high
- segregation at source facilities are few in India along w/ low level compliance of Municipal Solid Waste Management Rules.
- Lack of policy support.
Geothermal Energy
- harness energy stored in Eath's inner ore which comes out at certain places on the Crust
- where a higher geothermal gradient is created which is inc in temp with depth
- Hydrothermal convection is most common way of capturing
- In has a potential of 10GW in regions such as Himalayas, Lushai-Naga region, Andaman and Nicobar, Cambay, Son Narmada, Damodar Valley, Puga Velley etc
- Plan to set up geothermal plant in Ladakh
Fuel Cell
- Fuel cells generate electricity through an electrochemical reaction but not combustion. H2 and O2 are combined to generate electricity and water.
- Convert chem energy to electrical (DC)
- H2 used because no pollution from it
- can be used for small scale decentralised power generation
REN21 #body
- is the global renewable energy multi-stakeholder network
- connects wide range of key actors from Govt, international orgs etc
- non-profit association, provides policy relevant infor, platform for interconnection b/w stakeholders