Buildings are not buildings but energy forms. So what can you do about bringing sanity to such energy use when you build? It is useful to remember when you set out to build a house or an office building, a hotel or hospital, that every material that we use is expending energy in different forms, and is releasing carbon into the atmosphere.
In recent years we have come to call this 'grey' or 'embodied' energy. If you recall the tomato allegory from the previous edition of this column, when you next go to the vegetable market, look at vegetables you buy and ask yourself how far they have traveled for you to buy them. Typically in our towns and cities, they travel an average of 60 km. This transportation energy in the form of fossil fuels like diesel and petrol, add to the embodied energy of the vegetable. Fertilizers and pesticides that a farmer uses have also traveled very long distances for him to use for cultivation. There is then the electrical energy he uses for those inefficient irrigation pumpsets. All this adds up on the energy tab.
Similarly, when you buy bricks or concrete blocks for your house there is transport and manufacturing energy at various levels upstream that add to the energy used in your building. You could say that for the materials you use for floors, for steel and concrete you use for roofs and columns, the plastering of walls that need cement, the paints that use chemicals that not only need energy for manufacture but claim other energy values on raw materials, the wood that you use for windows and doors, the electrical cabling that uses copper, granite for kitchen slabs, the glass that you use for window panes the fans that you buy, the bulbs and tube lights that you buy ... every single such purchase has high embodied energy because they have traveled many miles and used a good deal of energy in the manufacture.
Here is a pie chart that is indicative of how high such energy consumption can be in the process of construction if you are building an air-conditioned office building or house. The rise in our need for greater luxury, and our greater ability to afford them with the money we earn has increased exponentially in recent years the extent of energy used by us for buildings, or for all the things we have learnt to use as gadgets and appliances. The figures are scary: in just the next twenty years we will build as much as we have built as buildings in the last 2000 years!
Time magazine reported some time ago, that in just the 1990s, the world produced as many cars as were made in the entire 20th century! Humans are the only one among over 8 million species that need fossil energy for their living; every other species sustains itself on the 'current sun' and renewable resources that make for their habitats.
Beyond the 'capital ecological cost' of energy expended at time of construction, is the use of energy when you begin to inhabit the place. This is dictated, of course, by the design approach you adopt for building. The higher the energy load that you factor at the time of construction, the greater will be the active energy cost for lighting, heating or cooling, and water heating. The more appliances we use in our kitchen the greater is the energy used. The more spaces we air-condition, the greater is the energy consumed when we live in the building.
Well, so how does one go about saving energy during construction or in the lifetime of a building when we live in it?
A lot of this has to do with your being sensitized to this concept of 'embodied energy'. As long as you can remember that every element in a house - from the finest particles that make the brick or the concrete block, to all other materials that we use - is living and breathing. Even stone lives! But their span of life is so much longer than ours that we think those are dead, inanimate. Stone lives for about a billion years. Sand lives for about 10,000 years. Limestone is formed over about 1 million years.
How far have those vegetables traveled to get to your market?
In designing your power and water needs, there are many things that you can do to focus on demand-side management. If you assume at the start of any such construction, that you have no power supply that you can expect from the power utility, you will then think differently. Necessity will then drive invention. It is hard for many to believe that there is no government that can offer you energy and water at your doorstep. But if you did come to terms with a reality that lies in the future where governments cannot bring these two resources at least in the same quantum as they did the past 50 years, then you will know how inventive you can become on demand-side management!
In any case, the day is not too far when you will be forced to stop relying on the government for water or energy, or for even collecting the waste from your doorstep. Imagine a day, and many days, when the waste from your house and many hundred other houses in your neighborhood is not collected by some agency! Waste will pile up, your road will stink, there will be mayhem. How does your city remain clean? Where does all the waste that you and I throw up go? When you start thinking about these, you will begin to see the need to make changes in the way you expect the government and other agencies to do their bit to help you.
In the next part of this series, we will engage on how you can save energy every day. We will also discuss how much energy can be saved on a daily basis or annually.