Three dimensions of sustainable design
When considering sustainable technologies it helps to think about three aspects, using the terms often used by the examination boards. In general, this involves asking the following types of question.

1. Environmental considerations
Looking at the whole life cycle of a product - from extracting raw materials, manufacturing, distribution, through to use and ultimate disposal - what is the environmental impact? What toxic emissions are there? How is energy generated and used? How much water is used? What is the environmental impact of any packaging?

2. Social considerations
Is the product really needed? How does it make life better for people? Is it culturally acceptable to the people who will use it? Does it build on the traditional wisdom and technology of the community? What is the impact on social relations? Will it enhance or diminish cultural diversity? Does it bring people together in a friendly way and encourage creativity? Does it have a long-term impact on future generations and the way they live together? If so, is this impact positive or negative? To answer these questions it is important to look at the whole life cycle of the product.

3. Economic considerations
Does making, using and disposing of the product create jobs? What sorts of jobs are created: do other jobs disappear? Who is employed? What is the economic impact on other people, now and in the future? Is the product fair-traded?

Moral questions
All the questions listed above are actually moral questions! When manufacturers decide to develop a product, they might just think about the profit they will make, and how to get the right product in the right place at the right price. Or they could also think about the long-term impact of the product on the environment, on people’s lives and on jobs. This is taking a moral position. A responsible manufacturer will try to ensure that the product has positive, long-term benefits, as well as meeting immediate needs.

Designers or design teams can also choose to take into account environmental, social and economic sustainability when making design decisions. The impact of most technological developments - be they products or processes - is ambiguous. For example, replacing paper bags with plastic ones at supermarkets uses far less oil (although the plastic bags are made from oil, the energy used to manufacture and transport them is less). But there has still been an impact from producing them and they can contribute towards litter. The question that designers need to ask is:
Is this new or modified product more or less sustainable than the one it is replacing? How can I make it more sustainable - environmentally, socially, economically? If it is a totally new product, what are the long term impacts?
These are all moral questions.

One of the SDA partners, ITDG, has worked with engineers and designers in Kenya to develop the small-scale hydro-electricity production. The mini case study shows how social, economic and environmental issues were all involved in the results of the project.

The penstock water pipe at Kerugoya, Kenya leading to the turbine house.

Inside the turbine house, preparing to turn on the generator.

Pico-hydro in Kenya
Most people in Kenya are not connected to mains electricity. This holds back a community’s ability to generate income and provide local services. Families have to rely on kerosene or batteries for light - both of these use non-renewable resources, cause pollution, they are manufactured abroad and have to be imported. Is it possible to use local resources to generate electricity, without causing pollution, and in a way that uses locally available materials and equipment? Can the solution also be socially and economically beneficial?

ITDG East Africa worked with Nottingham Trent University in the UK to develop a successful pico-hydro scheme in Kenya.

How it works
Water is diverted down a pipe (called the penstock) to fall through a vertical height (or head) to gather energy. The lower end of the penstock is attached to a turbine that is turned by the energy in the falling water. As the turbine spins it can be connected either directly to machines such as mills or presses, or to a generator to provide power for a small grid or battery charging.

Advantages of hydro power
• It does not cause pollution
• Power is usually available continuously on demand
• The energy available is predictable
• No fuel and limited maintenance are required: running costs are low compared with diesel power
• It is a long-lasting and robust technology: systems can last for 50 years or more without major new investments

ITDG’s pico-hydro project in Kenya shows that this technology is sustainable and affordable. Using a small spring to generate electricity the communities can watch TV and listen to the radio and children can do homework at night knowing that this technology is environmentally friendly. Money saved on buying kerosene and batteries can be used for other things, such as children’s education.

So, an environmentally friendly solution to the problem was found by using a renewable source of energy. It had economically beneficial results in terms of saving money. Some of the community have benefited socially from improved communication links. But, should some communities have it available while others have to continue to rely on kerosene? It’s a moral issue which is also part of the design equation.


What is sustainability?
What is sustainable development?
Definitions of sustainability
Three dimensions of sustainable design
Why things need to change
How do we add to problems?
What would a sustainable world be like?
Climate change
Datschefski’s principles of sustainable design