SOLAR Energy Manisha Goel Lecturer EE Deptt Govt

SOLAR Energy Manisha Goel, Lecturer, EE Deptt Govt. Polytechnic Manesar

“Solar Energy” l l l ‘Solar Energy’ or ‘Renewable Energy’ ‘Sustainability’ Solar or Renewable Energy – Solar ‘Radiant’ Energy – Wind Energy – Biomass Energy – Hydro and Wave Energy – Geothermal Energy **

Some ‘Solar’ Energy History § Solar Energy Use is Not New § In Use well before Our Discovery of Oil § Is the Source of our Coal and Oil

Augustin Mouchot’s largest ‘Sun Machine’, on display at the Universal Exposition in Paris, 1878

An Eneas ‘Sun Motor’ - 4 H. P. Solar Thermal Powered Steam Engine - on farm in Arizona, 1904

A Maryland Gentleman of the 1890’s enjoys a Hot Bath provided by a Climax Solar Water Heater l Climax Solar Water Heaters were sold extensively between 1890 and about 1920. l Later, the Day and Night Co. was a major supplier of solar hot water systems.

“Bell System Solar Battery Converts Sun’s Rays into Electricity”, Advertisement from Look Magazine, 1956.

Photovoltaics (PV)

How PV cells work

How ‘Silicon’ cells are made

Other Types of Solar Cells l Poly-crystal l Ribbon type ------> l Thin Film

Commercial Solar Cells l Single crystal silicon l Poly-Crystal Silicon l Thin Films

Emerging Technolgies Nano-solar techniques • Nano. Solar – Electrically Conductive Plastics • Konarka – Polymer and dye-sensitized solar cell have flexible cells about 5 % efficient

Cells, Modules and Arrays

Energy Tid-bit l The solar cells in the early 1950 s were about 0. 5 % efficient. Today a module is about 15 % efficient. l A 1 k. W system: § In 1950 = 2, 400 square feet § In 2005 = 80 Square feet

Typical PV Systems

1. 5 k. W PV Array - Vliet Residence, Austin TX, 2000

Building Integrated Photovoltaics (BIPV) Roof Shingles (many other examples)

PV System Installation on Roof of Commercial Building

BJ’s Wholesale Club & Sun Power Electric

Solar - Electric Car

PV Energy Tid-bit • • Energy required to manufacturer singlecrystal silicon PV modules will be produced by the module in 1. 5 to 2. 5 years. Thereafter the energy produced is a net gain. PV modules are expected to last beyond 20 years. Energy costs for some of the emerging technologies are expected to be lower.

Solar Thermal Swimming Pool Heating l Solar Cooking l Space Heating l Solar Hot Water l Solar Cooling l Ocean Thermal (Electric) l Solar Thermal (Electric) l

Swimming Pool Solar Heater, Austin, TX, late 1970’s

Collector for Solar Water Heating - Vliet Residence, Austin, TX, 1977

Passively Heated Asphalt Storage Tank - Midland, TX, mid - 1980’s

Tracking-Concentrating Collectors for UT Solar Cooling project, late 1970’s

Solar Furnace in French Pyrennes - Tracking Heliostats and Parabolic Reflector

Power Tower or Central Receiver type Solar Thermal Electric Power Generation

Thermal Energy Storage • • • Thermal energy storage (TES) systems heat or cool a storage medium and then use that hot or cold medium for heat transfer at a later point in time. Using thermal storage can reduce the size and initial cost of heating/cooling systems, lower energy costs, and reduce maintenance costs. If electricity costs more during the day than at night, thermal storage systems can reduce utility bills further. Two forms of TES systems are currently used. The first system used a material that changes phase, most commonly steam, water or ice. The second type just changes the temperature of a material, most commonly water. 30

Methods of Thermal Energy Storage • TES for Space Cooling: produce ice or chilled water at night for air conditioning during the day – Shifts cooling demands to off-peak times (less expensive in areas with real-time energy pricing) – May be used take advantage of “free” energy produced at night (like wind energy) • TES with Concentrated Solar Power: store energy in thermal fluid to use when sunlight is not available – Gives solar concentrating power plants more control over when electricity is produced • Seasonal TES – Long term energy storage – Store heat during the summer for use in the winter • Many other methods 31