A quick change can lead to significant savings. You reduce the wattage of any standard light by 70%, simply by unscrewing the incandescent light bulb and replacing it with a Compact Florescent Light (CFL).
Some people have strong objections to fluorescent lighting. That's because they remember what they were like a few years ago: they flickered, the light was harsh and they could not be dimmed. But the current generation of CFLs, much enhanced by digital technology, provide a steady light that's as warm as an incandescent bulb, and can be dimmed as needed.
The other objection to CFLs is that they can cost as much as $10 per bulb. But here's an example of how they still save you. A recent client of ours owned a furniture store that had 20 standard 100 watt incandescent light bulbs in the showroom.
Simply replacing these 20 lights with their CFL counterparts reaps amazing gains, with positive cash flow of over $500 the first year, and over $1,000 in savings in all years that follow.
The graph below shows these savings over ten years, based on conservative assumptions. Why ten years? Because that's how long, on average, it will be before these bulbs need changing!
The client saves $511 the first year (net, after purchase of CFLs), and $1,519 in the tenth year ($1,973 minus the annual energy cost of $454), with a cumulative ten year net savings of $11,448. That's quite a large ten year return on investment … for simply changing light bulbs!
What's the environmental impact of that change? On the basis of the current mix of energy sources used by the California energy utility PG&E, every kWh of electricity generates 0.524 lbs CO2. Based upon the energy reductions listed in the graph, we would reduce carbon emissions by 29,050 pounds over ten years. This is roughly equivalent to taking one car off the road for one year. Who says it isn't easy being green?
The classic case of a major sustainability project that proved its worth is that of Adobe Systems of San Jose, which embarked on an ambitious energy saving project following the California energy crisis of 2001. Over several years, they invested $1.4 million in energy and water retrofits. This sounds like a lot, but they are saving $1.2 million in energy costs - every year. Some highlights of the project will give you an idea of how broad the scope is for resource efficiency:
- Automating the garage exhaust fans so that they cut off when there were no cars cost $100,000, but resulted in annual savings of $67,000.
- Retrofitting the garage lighting on the same principle required an investment of $158,000, and resulted in annual savings of $139,000. Plus, they got a $41,000 tax rebate.
- Waterless urinals in men's restrooms, and motion sensor valves on sinks and toilets, cut water use by 22%.
- Changing the landscape design of the outside gardens reduced irrigation by 76%.
- Electricity use has been cut 37% and natural gas by 41%.
- Composting and recycling have cut solid waste by 94%.
- CO2 emissions have been cut by more than a fifth.
The sustainability philosophy at Adobe goes further than just the building. Employees have been encouraged to join in. Adobe provides employee incentives to promote the use of transportation alternatives. For example, locked bike cages inside the Adobe towers encourage biking to work. Some 20% of the 2,600 employees on the San Jose campus use alternative forms of commuting; the average in Silicon Valley is around 4%.