Energy Star program started by USEPA
Energy star is a energy efficiency-labeling program that is operated both by United States Department of Energy and United States Environmental Protection Agency (US EPA). The program is usually voluntary and it started in 1992. It is now a leading brand internationally for production of products that are efficient in energy. The central role of Energy star in regional, national and international development in energy programs requires a process that is open whereby the achievements of the program as at today as well as the anticipated future savings are shared together with stakeholders that are committed.
The energy star comprises of four distinct areas namely products, buildings and industrial plants, home performance and new homes.The program applies a bottom-up model. This is due to the awareness of the uncertainty for every individual product types contributions to the impacts of energy star. This is to mean inaccuracies however small they are add up to the overall and that any product with an inaccuracy in products which have large savings in energy affect the overall results significantly. This uncertainty is addressed by running sensitivity test on key variables like Energy star unit for sales, the prices of energy and factors on carbon emissions. More emphasis is put on office equipment although input data on others is regularly updated. This is due to the underlying potential in saving energy which is high in addition to having consumer electronics where patterns in usage tend to be more uncertain.
From the year 2006 it is notable that products labeled Energy star saved up to 4.8 EJ of primary energy this amounted to about $47billion in terms of bills of energy and then avoided an equivalent of 82 Tg C. Six of the products labeled Energy star have contributed to reduction of carbon dioxide amounting to 70%.
US Green Building’s Council’s LEED Rating System
The buildings we use have some considerable effect on environment. They have impact on the natural environment, health of men and the economy at large. These adverse impacts prompted the development of green buildings. The main aim of this was to convert the environment which was built in creation of energy efficient buildings that are as well healthy and productive. The green building trend has become more common whereby consumers, communities, builders as well as government is becoming a bit sensitive to the effects of the buildings have on urban life as well as the locals, regional and the entire planet.
The LEED green building rating system was put in place by U.S. Green Building council. Its main aim was certification of green building. The need for a strong certification system became apparent with the increase in the number of green building initiatives. This was needed to show that the buildings were actually green and also lend a tool to the owners to get measurable impact on their building performance.
Advantages
The market of green building is getting more competitive and the increased costs in building are taken care of by the green buildings’ saving of energy. The buildings constructed with this certification are sustainable. It has gained world wide acceptance. They have helped in saving the environment where we live in hence promoting a healthy living.
Drawbacks
They are associated with an extra cost as compared to the conventional one which is a burden to many. Also an additional cost is incurred in undertaking the certification with LEED. The structure of design of the building may at times be limited and keen planning and reviewing of all design must be done to ensure that green requirements are met.
Heat pump
A heat pump is used in assisting in cooling and heating systems at home and also in commercial buildings. The device gives out hot or cold air depending on the need. It basically moves heat from the source which has a lower temperature to another destination which can be referred to as the heat sink which has higher temperature condition. This is done using a high temperature source of heat.
It can be used both in cooling as well as heating. Examples of these devices are refrigerator, freezers and air conditioners. Also some reversible cycle heat pumps for building space heating are examples of heat pumps.
In the refrigerator heat is usually drawn from the source and the evaporator helps the working fluid to evaporate. Then heat release takes place leading to cooling down of the area. With the release of the heat to cool the air, the condenser condenses the working fluid. A reversing valve creates cool air as this occurs hence the working fluid direction is reversed with the aim of starting the process over again. As the refrigerator does heat pump equally removes heat from the source aiming at keeping the area cool.
Heat pump uses less energy than straightforward electric heating. This is because heat pump just separates heat from some heat sources like water, air and soil when heating and when cooling heat is discharged. This process is reversible and it means that heat discharged when cooling can be used when heating hence little energy is spend unlike the electric heating where each process uses its own energy.
Reference
Horowitz, M. (2007). Changes in electricity demand in the united states from the 1970s-2003: The energy journal volume 28, Number 3.
Langley, B.C. (2001). Heat pump technology 3rd Ed. New Jersey: Prentice Hall Publishers
Yellamraju, V. (2010). LEED-New construction project management. Canada: McGraw-Hil
