Achieving Energy Independence with Off-grid, Battery-based Solar Energy Systems Vinod Tiwari Director Renewable Power Solutions (Telectron LLC)
Introduction to Solar Energy We need Solar Energy, because of various reason like Climate change, Health issues and Increasing Utility power cost. Fossil fuels are non-renewable energy resources. Their supply is limited and they will eventually run out. The energy required for the entire planet for 24 years can be obtained by sunlight in just 24 hours. I d put my money on the sun and solar energy. What a source of power! I hope we don t have to wait until oil and coal run out before we tackle that. Thomas Edison, 1931 Solar can be designed or sized to supply power to DC and/or AC electrical loads as per the various application demand.
Grid-connected PV System
Off Grid- System
WHY Off- Grid Solar To achieve Complete Independence from external energy supply and electricity cost to have power 24X7, even during no sunshine. Picture Courtesy : To Contribute to the environment for green energy without leaving pollution foot print to save mother earth A Go Green Concept. ONLY option for Remote Location, where traditional grid power is NOT available and cannot reach. Fossil fuels release carbon dioxide when they burn, which adds to the greenhouse effect and increases Global warming. Solar s carbon foot print is 25% lower than that of fossil fuel s power plant. Picture Courtesy : Solar City.com
Major Components 1. P.V Module Solar electric collector modules connected together to make Solar Array. 2. Solar Charge Controller Regulate and Manage the power going to battery bank from the Solar Array. 3. Energy Storage Device Batteries are used to store DC power energy produced by Solar Array to supply during night. 4. Solar Inverter - Converts the DC power into AC power to supply actual AC electric loads.
PV Solar Types 1. Mono Crystalline Silicon Solar PV a. Most Efficient (14-18%) b. Proven Technology c. Bit Expensive 2. Poly Crystalline Silicon Solar PV a. Comparative less efficient (<14%) b. Proven Technology c. Comparative less expensive 3. Thin Film Solar PV a. Portable / Lightweight b. Good Efficient (Upto 20%) c. New Technology
PV Solar Combination To achieve the desired Solar Power below combination can be used. Series Combination:- (3 x 250W/36V/6.9A) WATTAGE are ADDITIVE VOLTAGE are ADDITIVE CURRENT remains CONSTANT Total Power = 750W/108V/6.9A Parallel Combination:- (3 x 250W/36V/6.9A) WATTAGE are ADDITIVE VOLTAGE remains CONSTANT CURRENT are ADDITIVE Total Power = 750W/36V/20.7A
Tilt/Direction/Shading on Modules TILT - For a fixed array the tilt angle is the angle from horizontal of the photovoltaic modules, as per location. For example Optimum Tilt angle for Abu Dhabi is 24 Deg. C by facing towards SOUTH. DIRECTION In the Northern hemisphere best direction is to face Solar Panels is SOUTH. In the Southern hemisphere best direction is to face Solar Panels is NORTH. SHADING Depends on orientation of internal module circuitry relative to the orientation of the shading. SHADING can half or even completely eliminate the output of a solar array!
Charge Controller Types Manage the power and ensure that batteries are not overcharged Ensure that power doesn t run backwards to solar array from battery. 1. MPPT Controller a. Maximum Power Point Tracking Controller. b. MPPT harvest more power from solar array. c. Establish an indirect connection both PV array and Battery bank. d. Also acts as DC/DC voltage converter to convert excess voltage into current to reduce the energy loses. 2. PWM a. Pulse Width Modulation Controller. b. Acts as a switch to connect solar array to the battery. c. Voltage of the solar array is pulled down to nearer voltage of battery for charging. d. Efficiency is also on lesser side. Picture Courtesy : Morning Star
Energy Storage Device - Types 1. Solar Power can be stored in battery bank and can be utilized to power AC/DC loads during NO Sun-hours. 2. For solar application, majorly Lead Acid battery are being used. 3. Battery bank capacity is required to be sized as per the autonomy requirement (72 hours is majorly used for industrial application) 4. Battery capacity can be achieved by the combination of Serial/ Parallel connection as per the design voltage/amp-hour. 5. VRLA battery are temperature sensitive and need to be maintained as recommended by manufacturer.
AGM Technology Valve Regulated Lead Acid Battery for Photovoltaic Application :- 1. Excellent cycle life for photovoltaic application 2. Deep discharge recovery 3. Wide band of temperature operation 4. No separate room required 5. Better recombination efficiency 6. Simple cell replacement capability 7. Excellent heat dissipation in high temperature 8. No need of toping up being Maintenance free Picture Courtesy : GNB (Exide)
GEL Technology VRLA battery, in which electrolyte is in the form of GEL 1. Exceptional Cycling Performance 2. Very low discharge rate and long shelf life 3. Lowest energy consumption 4. Strong Tubular Plate technology 5. Horizontal mounting possible 6. Completely recyclable 7. Maintenance free (No topping up) Picture Courtesy : GNB (Exide)
Solar Inverter A solar inverter is an electronic device or circuitry that changes direct current (DC) to alternating current (AC). The inverter does not produce any power; the power is provided by the DC source. A power inverter can be entirely electronic. Solar inverters may be classified broadly into two types: 1. Stand-alone Inverters Used in isolated systems, where the inverter draws its DC energy from batteries charged by photovoltaic arrays. 2. Grid-tie Inverters Designed to shutdown automatically upon loss of utility supply, for safety reasons. They do not provide backup power during utility outages. Picture Courtesy : PIKO
Various Applications Solar ATM Tourism Water Pumping Street Lighting
Operation and Maintenance Like any power plant, a Solar power plant requires proper Maintenance. As Solar Power System becomes older, operation and maintenance becomes more important for improved Output and Performance. A well-maintained solar installation can actually perform 10 to 30% better. Regular to analyze whether it is producing the amount of power for it was designed. On average, regular solar array cleaning will increase annual solar energy production by 5 to 10%. Out of reactive and preventive maintenance, Preventive offers the best balance of failure and maintenance costs.
Case Study Solar Energy System Client/ End-Customer - Govt. Organization, UAE Installation Locations: - Desert of - Al Ain and N. Emirates Eligibility required - Company should have capability of Design/Engineering/Supply Integrate/Storage/Battery Charge Installation/Testing/Commission Telectron s Scope - 60 W / 24 V DC 188 Nos. 150 W / 48 V DC 32 Nos. 4500 W / 230 V AC 43 Nos. Project was successfully Tested, Commissioned and proved to be as one of the highly appreciated project, as was executed by Telectron. Picture Courtesy : Telectron
Conclusions Are you fed-up with utility company? Are you searching for alternate solution? Are you looking for energy independence? Do you want sunlight at night? Do you want to utilize available sun power? Do you want to contribute to the environment?
Conclusions GO Green.. GO Clean.. GO Solar..
Heading THANK YOU FOR ATTENDING THE PRESENTATION