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

Basic parts of a wind energy system

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.

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.

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.

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.

• 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.

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

• 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.

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.

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.

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.

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.

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

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.