Resources are renewable if they replace themselves naturally or if people can grow or raise continuous supplies of them. Some renewable resources are forests and animal life. People are important in determining how resources are used and renewed. For example, lumber companies can carefully choose which trees to cut and how many. They can also plant a harvested area with new trees to help renew forest and resources.
The earth’s crust, however, has many non-renewable resources -- resources that can never be replaced. Such resources include most minerals and fossil fuels. People may recycle, or reuse, these resources, but natural growth or human skill cannot replace them.
People also affect the quality of the basic elements of air, water, and soil. These resources cannot be replaced but can be conserved, or protected, through proper management.
Minerals form most of the earth’s land resources and are often found naturally in the ores that people mine. Many of the earth’s more than 2,000 different minerals help support or improve human life, and so people value them. Certain mineral resources provide important medicines and building materials. Factories often mix minerals to make different kinds of materials. For example, factories blend iron ore with alloys such as manganese to produce steel. Minerals in the form of fertilizers aid in producing greater amounts of food.
Fossil fuels are an especially valued resource today. Because these fuels were formed over thousands of lifetimes, they are considered non-renewable. Such resources provide heat, light, and the energy necessary to run machines. They are also used in the manufacturing of plastics, fertilizers, and other goods.
What is efficiency and how energy efficiency is measured?
To explain efficiency, we shall take the example of power consumed by say a computer. The efficiency of a computer power supply is its output power divided by its input power.
The remaining power is converted into heat. For instance, a 600-watt power supply with 60% efficiency running at full load would draw 1000 W from the mains and would therefore waste 400W as heat. On the other hand a 600- watt power supply with 80% efficiency running at full load would draw 750 W from the mains and would therefore waste only 150W as heat.
For a given power supply, efficiency varies depending on how much power is being delivered. Supplies are typically most efficient at between half and three quarters load, much less efficient at low load, and somewhat less efficient at maximum load.
It is easier to achieve the higher efficiency levels for higher wattage supplies. Typical computer power supplies may have power factors as low as 0.5 to 0.6. The higher power factor reduces the peak current draw, reducing load on the circuit or on an uninterruptible power supply.
Reducing the heat output of the computer helps reduce noise, since fans do not have to spin as fast to cool the computer. Reduced heat and resulting lower cooling demands may increase computer reliability.
The testing conditions may give an unrealistic expectation of efficiency for heavily loaded, high power (rated much larger than 300 W) supplies. A heavily loaded power supply and the computer it is powering generate significant amounts of heat, which may raise the power supply temperature, which is likely to decrease its efficiency. Since power supplies are certified at room temperature, this effect is not taken into account.
The Leadership in Energy and Environmental Design (LEED) certification for buildings, introduced in 2000 has rapidly grown in popularity and demand. Information about hundreds of green commercial building projects may be found on the internet, many with impressive claims about their projected energy consumption. But obtaining actual energy consumption data for green commercial buildings is difficult.
Energy efficiency is but one of many criteria for LEED. Building certification and credits for energy efficiency are awarded based on design simulations, not measured building energy performance. There has been little work on validating whether projections of performance correspond to actual building performance.
What goals can we set at the national level in controlling energy consumption?
An interesting study was conducted five years ago. A 2000-watt Society: Case Study in Switzerland
A study was conducted in Switzerland on the per capital consumption of electricity in 2008. Breakdown of average energy consumption of 5.1 kW by a Swiss person was
- 1500 watts for living and office space (this includesheat and hot water)
- 1100 watts for food and consumer discretionary (including transportation of these to the point of sale)
- 600 watts for electricity
- 500 watts for automobile travel
- 250 watts for air travel
- 150 watts for public transportation
- 900 watts for public infrastructure
Researchers in Switzerland believe that a vision of 2000 watt society is achievable, despite a projected 65% increase in economic growth by 2050, by using new low-carbon technologies and techniques.
It is envisaged that achieving the aim of a 2000-watt society will require, amongst other measures, a complete reinvestment in the country’s capital assets; refurbishment of the nation’s building stock to bring it up to low energy building standards; significant improvements in the efficiency of road transport, aviation and energy-intensive material use; the possible introduction of high-speed maglev trains; the use of renewable energy sources, district heating, micro-generation and related technologies; and a refocusing of research into new priority areas.
As a result of the intensified research and development effort required, it is hoped that Switzerland will become a leader in the technologies involved. Indeed, the idea has a great deal of government backing, due to fears about climate change.
Water …Water …Everywhere Not a drop to drink.
“Water, water, everywhere,
And all the boards did shrink;
Water, water, everywhere,
Nor any drop to drink.”
- Samuel Taylor Coleridge, The Rime of the Ancient Mariner
No doubt, water scarcity remains a major threat to public health – and a major opportunity to sustainable business development.
China, which represents one-fifth of the world’s population but possesses just 6 percent of the global fresh water supply, plans to increase its seawater desalination capacity threefold by 2015. If the country hits its goals, it will by 2020 produce enough fresh water using reverse osmosis (RO) to supply fresh drinking water for about 100 million residents.
Water efficiency is the smart use of our water resources through water-saving technologies and simple steps we can all take around the house. Using water efficiently will help ensure reliable water supplies today and for future generations.
Water Efficiency & the Environment: When reservoir water levels get lower and ground water tables drop, water supplies, human health, and the environment are put at serious risk. For example, lower water levels can contribute to higher concentrations of natural and human pollutants.
Less water going down the drain means more water available in the lakes, rivers and streams that we use for recreation and wildlife uses to survive. Using water more efficiently helps maintain supplies at safe levels, protecting human health and the environment. Water is one of the natural resources that is in very limited supply especially in the Middle East. Natural freshwater resources are very few.
Drops to Watts: Save Water, Save Energy
It takes a considerable amount of energy to deliver and treat the water you use every day. For example, letting your faucet run for five minutes uses about as much energy as letting a 60-watt light bulb run for 22 hours. Heating water for bathing, shaving, cooking, and cleaning also requires a lot of energy. Homes with electric water heaters, for example, spend one-quarter of their electric bill just to heat water.
With climate change concerns, pervasive droughts, and high energy prices across the country, nearly everyone is looking for ways to conserve resources and cut costs. The good news is that by using a little “water sense” we can all save water, energy, and money.