The first step that the Energy Conscious people have to take, is to assess the effectiveness of energy saving devices and materials. What is embodied Energy? Wikipedia says: “Embodied Energy is the sum of all the energy required to produce any goods or services, considered as if that energy was incorporated or ’embodied’ in the product itself.” sda-uk.org says: “The embodied energy of a material refers to the energy used to extract, process and refine it before use in product manufacture. Therefore, a correlation exists between the number and type of processing steps and the embodied energy of materials. For example, the fewer and simpler the extraction, processing and refining steps involved in a material’s production, the lower its embodied energy.
The embodied energy of a material is often reflected in its price.” Embodied Energy of LED lamps: What does this mean to us? Let us suppose that your electricity usage is 400 units or 400 kWh. And you wish to reduce this. As a first step, you may wish to replace your incandescent lamps with more expensive CFL or LED lights. Though CFL lamps were much touted initially, now people frown on them for their toxic mercury content. So it’s LED lights that you would be investigating. Normally, you may look at your costs. You may say, “each incandescent bulb uses 100W and I need to switch it on for 5 hours per day. That is 500 Watt hours or 0.5 kWh or 0.5 units per day or 15 units a month. If I replace this by a 22W Philips LED Light (1780 lumens), then I use only 3.3 units a month. If each unit of electricity costs me Rs 6, then I am saving Rs 72 per month! And this bulb lasts for 50,000 hours compared to 1200 hours of an incandescent bulb. That means it lasts about 40 times longer. So if I can get an LED light for the right price, I can save a lot of money!” But this is not the whole story. If you are conscious of the the cost to the environment, then you must look at the embodied energy cost. GreenLivingPedia says: “Until late 2009, no one knew if the production of LED lamps required more energy than needed for standard incandescent bulbs. While it is indisputable that LEDs use a fraction of the electricity of a regular bulb to create the same amount of light, if more energy were used in the manufacturing and distribution process, then the lighting industry could be traveling down a technological dead end. The study results show that over the entire life of the bulb — from manufacturing to disposal — the energy used for incandescent bulbs is almost five times that used for CF and LED lamps.” So if the study is valid, it means that the embodied energy of an equivalent number of incandescent bulbs is greater than the embodied energy in an LED Light. Embodied Energy and Building Materials: Embodied energy can be the equivalent of many years of operational energy. The CanadianArchitect web-site gives a chart of the embodies energy of different building materials. They also have a concept of “the recurring embodied energy in buildings which represents the non-renewable energy consumed to maintain, repair, restore, refurbish or replace materials, components or systems during the life of the building.” The featured image is from the Institute of Wood Technology Museum at Bangalore.