HomeSouthern AfricaLiving off-grid

Living off-grid

1              Introduction

The residential sector in South Africa consumes 17% of the electrical energy. More than 70% of this electricity is generated using fossil fuels which contribute immensely to environmental pollution and global warming.

SolarThe South African Government, through the passing of the Energy Bill, the Renewable Energy White Paper, and the Energy Consumption Management, Measurement and Reporting Regulation under the Energy Act of 2008, amongst others, has become increasingly active in addressing the issues of electricity outages and the more efficient use of existing resources.

The use of renewable energy resources and energy efficient measures complementing fossil fuels is expected to result in uninterrupted power supply and more importantly, a reduction of gaseous pollutants. Solar energy is one of the renewable energy resources that is increasingly being used to supply household demands for thermal and electrical energy.

The energy efficient building integrated photovoltaic (EE BIPV) house currently being constructed at the University of Fort Hare, Alice campus, is part of the initiative to utilize renewable energies and showcase solar energy as an alternative to fossil fuel utilization in households. This project is spearheaded by the director of the Fort Hare Institute of Technology (FHIT) Professor Edson L Meyer and PhD student, Mr. Sosten Ziuku.


2              House Design features

2.1          Passive solar design

The concept of sustainable energy house design is strongly based on the use of renewable energy resources in place of fossil fuels. This entails the use of climatic conditions to design a climate sensitive building which, for all intends and purposes, discourages energy utilization processes that cause global warming.

In South Africa, the sun passes almost directly over-head at noon in summer, whilst in winter, its path is low in the northern sky. With large windows and clerestory windows located on the north facing side of the house, the lower winter sun is allowed to heat both the front and rear of the inside of the house. Furthermore, sufficient window overhangs protects the north facing windows from the high summer sun to enhance cooling through natural ventilation. Previous studies employing passive solar heating and cooling, proved that this technique has great potential to provide a safe, healthy and thermally comfortable indoor environment.


2.2          Building integrated photovoltaics

Photovoltaic (PV) panels are mounted on the north facing roof in such a way that they replace conventional roofing material. The PV panels then act as a building envelope and also supply the electrical energy requirements of the house. The PV solar system has a maximum power output of 3 800 Watt, sufficient to meet all the electrical energy requirements of the building. Energy Efficient electrical appliances are also used in the house. This implies that the EE BIPV house can be completely independent of the national utility grid. In fact, a second phase to the study is to sell excess power generated to the national utility grid!


2.3          Solar water heating

Only about 15% of solar energy received from the sun, is converted into useful electricity. Some 60% of the remaining energy is used to heat water in a solar water geyser. For this experiment, a 200 liter solar water heater is used to meet all the hot water requirements.


3              Additional Information

The EE BIPV house is expected to be completed towards the end of November. The accompanying figure shows the current building status.

The winning name will be a catchy phrase, name or acronym in any one of the 11 official languages, portraying the house as energy efficient and independent of the grid. Other characteristics that should be portrayed are zero carbon emission, renewable or solar energy and self sustainability.