"Achieving Energy Independence with Off-grid, Battery-based Solar Energy Systems" A Presentation by Vinod Tiwari at 'Dubai World Trade Center' in November 2017.

1. Achieving Energy Independence with Off-grid,
Battery-based Solar Energy Systems
Vinod Tiwari
Director – Renewable Power Solutions
(Telectron LLC)

2. Introduction to Solar Energy
“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
The energy required for the entire planet for 24 years can be obtained by
sunlight in
We need Solar Energy, because of various reason like – Climate change,
Health issues and Increasing Utility power cost.
Solar can be designed or sized to supply power to DC and/or AC electrical
loads as per the various application demand.
Fossil fuels are non-renewable energy resources. Their supply is limited
and they will eventually run out.
just 24 hours.

3. On-Grid Solar Energy System

4. Off Grid- Solar Energy System

5. WHY Off- Grid Solar
To achieve Complete Independence from external energy supply and
electricity cost to have power 24X7, even during no sunshine.
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.
Solar’s carbon foot print is 25% lower than that of fossil fuel’s power
plant.
Fossil fuels release carbon dioxide when they burn, which adds to the
greenhouse effect and increases Global warming.
Picture Courtesy :
Picture Courtesy : Solar City.com

6. 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.

7. 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

8. 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

9. 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.
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!
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.

10. Charge Controller – Types
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.
 Manage the power and ensure that batteries are not overcharged
 Ensure that power doesn’t run backwards to solar array from battery.
Picture Courtesy : Morning Star

11. 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.

12. 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)

13. 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)

14. 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

15. Various Applications
Solar ATM
Street Lighting
Tourism
Water Pumping

16. 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.

17. 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

18. Conclusions
Are you searching for
alternate solution?
Do you want to
contribute to the
environment?
Do you want to utilize
available sun power?
Do you want sunlight
at night?
Are you fed-up with
utility company?
Are you looking for
energy
independence?

19. Conclusions
GO Green..
GO Clean..
GO Solar..

20. HeadingTHANK YOU
FOR ATTENDING THE PRESENTATION