Presentation by Leon Gouws of Kestrel Renewable Energy at the CHOICES project community energy workshops in Somerset East, Pearston and Cookhouse communities, Blue Crane Route Municipality in South Africa’s Eastern Cape, held in February and March 2013. The presentation covers aspects of wind energy technology. More information about Kestrel Renewable Energy: http://www.kestrelwind.co.za/ Further details of the CHOICES project: http://www.iied.org/choices-community-energy-project-south-africa

1. Wind Energy
Wind power can be harnessed for both generation of electricity (wind generators) and
irrigation (wind pumps). The amount of energy produced from wind energy
technologies is variable because it is dependent on the wind speed, which is constantly
changing.
RENEWABLE ENERGY
SOLUTIONS

2. Basic parts of a wind energy system

3. Basic parts of a wind energy system
Home wind energy systems generally comprise a rotor, a generator or alternator
mounted on a frame, a tail (usually), a tower, wiring, and the "balance of system"
components: controllers, inverters, and/or batteries. Through the spinning blades, the
rotor captures the kinetic energy of the wind and converts it into rotary
motion to drive the generator.
Wind Turbine
Most turbines manufactured today are horizontal axis upwind machines that have two
or three blades, which
are usually made of a composite material such as fiberglass. The amount of power a
turbine will produce is determined primarily by the diameter of its rotor. The diameter
of the rotor defines its "swept area," or
the quantity of wind intercepted by the turbine. The turbine's frame is the structure
onto which the rotor, generator, and tail are attached. The tail keeps the turbine facing
into the wind.

4. Tower
Because wind speeds increase with height, the turbine is mounted on a
tower. In general, the higher the tower, the more power the wind system can
produce. The tower also raises the turbine above the air turbulence that can
exist close to the ground because of obstructions such as hills, buildings, and
trees. A general rule of thumb is to install a wind turbine on a tower with the
bottom of the rotor blades at least 9 meters above any obstacle that is within
90 meters of the tower. Relatively small investments in increased tower
height can yield very high rates of return in power production.

5. Hybrid renewable energy systems
Hybrid installations combine the use of wind turbines and photovoltaic systems (solar
panels) to generate electricity. These types of installations provide a more consistent
year-round supply because it is possible to generate output from one resource when
the other is not available. During the winter months and at night when solar energy is
less readily available, wind energy tends to be more prevalent.

6. Applications
Renewable energy can be used in different
applications – off grid, grid connected, water
pumping and telecommunications.
• Off Grid Systems
- No connection to the electricity distribution
system (the grid).
- Provides reliable power form the wind and/or sun
which is stored in batteries.
- A charge controller ensures that the batteries are
charged correctly and helps prolong their life.
- When the battery bank becomes full, the charge
controller will dissipate the incoming energy to a
divert resistor.
- An inverter provides utility-grade electricity.

7. • Grid Connected Systems
- Connected to the electricity distribution system
(the grid).
- In synchronising with the grid, the need for storage
devices, e.g. batteries, are eliminated.
- When the renewable energy system cannot deliver
the amount of energy required, the default power
will be supplied via grid power.
- Excess electricity produced is fed back into the grid.
- A power conditioning unit (grid tie inverter) makes
the turbine output electrically compatible with the
utility grid.

8. Potential :
Small wind turbines power potential – total home system
energy needs – battery based:
farmhouses or buildings, including worker houses
Pump water
Clinics
Crèches
Reduce dependence on the grid and improve
reliability
Limitations:
• Wind continuity - Need to make a hybrid system with
solar PV
Advantages of wind renewable energy solutions
• help you avoid the high cost of electricity
• supply electricity to areas where no grid electricity is available
• prevent power interruptions
• help you lower your carbon footprint
ADDED IN TO KESTREL MATERIAL

9. • Water Pumping Systems
- Water pumping systems uses electricity generated
by renewable energy sources (wind and/or sun) to
pump water from a source to where the dam or
reservoir is located.
- The wind turbine is placed where there is most
wind, it does not have to be directly above the
pump/well.
- Can deliver up to twice as much water as
traditional mechanical water pumping equipment
and also does this at low wind speeds.
- The Kestrel Water Pumping system combines the
world renowned Grundfos SQ Flex pump with 1
kW wind turbine to deliver up to 75,000L of water
per day.
- Kestrel will use head height and wind availability
data to calculate expected water delivery.

10. Cost
It is impossible to give an exact amount for a renewable energy system, as every
application has different components and every client has different energy needs.
A complete installed system can range from R70 000 for smaller systems to R150 000
for bigger systems.
Why use Kestrel?
• Kestrel Renewable Energy is a subsidiary of Eveready (Pty) Ltd. South Africa’s iconic
battery brand.
• Kestrel wind turbines are locally manufactured at the Eveready factory in Port
Elizabeth, South Africa.
• Our world class manufacturing facilities are ISO 9001, 14001 and OHSAS 18001
certified.
• We have sold over 700 turbines worldwide.
• Our turbines are the first in its class to be UK (MCS) and USA (SWCC) certified,
which allows them to qualify for incentives in certain countries.

11. KESTREL RENEWABLE ENERGY CASE STUDY
LANGBOS CRECHE, ADDO, EASTERN CAPE
Langbos Crèche is situated in an informal settlement approximately 3km from Addo.
The Crèche has no access to grid electricity and previously ran the lights of a generator. The generator
was often faulty and the school didn’t always have money for petrol to run the generator.
Kestrel did an analysis of the site and found that a 10kWh per day hybrid systm consisting of a 1kW
wind turbine and 6 230W solar panels would be best suited for the crèche’s needs. Kestrel installed the
renewable energy system, changed the lights from 52W bulbs to 31W energy saver bulbs and installed
lighting and socket outlets in new class rooms.

12. The crèche currently runs the following of the Kestrel renewable energy system:
6 x 4ft, 31W twin fluorescent lights
6 x 15W lights
4 x 23W lights
1 x fridge
1 x microwave
1 x television
1 x kettle
1 x toaster
The Kestrel 10kWh hybrid off-grid systems consisting of the following components:
1 x e300i 48V 1kW wind turbine
6 x 230W solar panels
1 x Midnight Classic (solar MPPT) controller
1 x Wind turbine charge controller
A 48V 260 A.h AGM battery bank
The battery bank (when fully charged) has a 7.5kW standby capacity.

13. CASE STUDY
James Louis Hollenbagh
Case Study:
This hybrid system was installed to replace the use of a generator. No Eskom power were
available on this farm and the use of a generator was very expensive. All the electricity
generated is used to run the farm house.

14. Kobus Bergh – Kestrel Hybrid Waterpumping System
Installation Date:December 2011
Case Study:
This hybrid system is used to power a 1.2-3 grundfos waterpump. The pump pumps water
out of a borehole which is used as drinking water for camels and sheep and for domestic
purposes. The average water delivery is 1200 liters per hour

15. Kestrel Power for Farm Workers
Installation Date:January 2009
Purpose:Supply wind power to the farm workers’ houses
Case Study:
One Kestrel e220 (48V) wind turbine with a charge controller system regulator, a
divert resistor and batteries.