*Alfredo Sotolongo
In recent issues I have written comments regarding the different equipment and / or systems available to conserve energy when designing an air conditioning system.
In this edition I would like to concentrate on how you can conceive a building that complies with the so-called Green concept which means designing new buildings, remodeling existing buildings and operating those buildings in such a way that energy consumption, water expenditure, etc. is minimized. Buildings in which being environmentally responsible conditions are improved achieving a healthy environment that allows a better quality of life for the occupants.
Buildings, whether residential or commercial, greatly impact the environment. They consume approximately 30% of all energy, 60% of electricity and a large amount of drinking water only when discharging toilets. The Green concept can considerably reduce these negative environmental effects and also entails other benefits such as minimizing the cost of operation, increasing the production capacity of the people who work in them and achieving better indoor air quality.
With the purpose of uniting all those interested in achieving the Green concept, in 1993 the Council for Green Buildings of the United States, known by the acronym in English USGBC, was founded. When the members realized that buildings, mainly commercial ones, made such a marked impact on the environment, they decided to organize a system to define and measure green buildings. They developed the LEED method that translates as Leadership in Energy and Environmental Design, with which it is possible to measure how green a building is.
What it's all about
The measurement is based on points that are assigned to the building depending on what was taken into consideration at the time of design to minimize the impact on the environment. To apply for Green Building certification it is first necessary to meet a series of requirements established by the Council (USGBC) and once those requirements are met, the application process for certification begins.
The categories on which they base the score are as follows:
1. Maintenance of the Infrastructure.
2. Use of Water.
3. Energy and Atmosphere.
4.Materials.
5.Quality of the Indoor Environment.
6. Innovations in Operation and Improvements.
There are applications of equipment or materials that could help score in more than one of these categories.
Because of the length of the application process to certify a building as Green, I'm going to focus on what most directly relates to us, the air conditioning system. Although points may be obtained in more than one of the categories, Energy and Atmosphere is the one that is most directly related to our industry. Within this category are, among others, the following requirements and justifications to accumulate points:
1.How the systems are put into operation.
2.Optimization of energy consumption.
3.Education of maintenance personnel.
4.Monitoring of systems.
5.Additional protection to ozone.
6. Measurement of the efficiency of the systems and reporting of emissions.
Like everything in our industry, ASHRAE contributes several Guidelines and Standards by which the Council is guided to determine the prerequisites and how to assign points, among which are Guide 0-2005 "The Commissioning Process", Guide 1-1996 "The Process of Commissioning of Air Conditioning and Ventilation System" and Standard 100-1995 "Energy Conservation in Existing Buildings".
Many of the manufacturers of equipment and materials used in air conditioning systems have developed products that, when applied, contribute to obtaining points to certify the building where they are installed as Green. Among the examples that I can cite are:
to. In the case of the central cold water plant, Armstrong has managed, applying a control algorithm with state-of-the-art technology, to optimize the operation of all components at the same time, without having to depend on the behavior of another which makes the reaction of the system much faster to changes in thermal load.
b. In variable air volume systems, Thermafuser has managed to reduce the consumption of the fan motor of the air conditioning unit, measurement and reporting of the variables and verification of consumption.
c. In supplying outdoor air to maintain indoor air quality without increasing energy consumption, ConServ has achieved this by recovering energy from both sensitive heat and latent heat.
Awareness and budget
Today there is awareness among engineers who design air conditioning to make systems as efficient as possible, however, very few investors are aware of this need and often put obstacles to engineers when they find that to achieve it is necessary to invest a little more in their building.
However, when some time passes and they receive the bills for energy, they ask their engineers to look for alternatives to minimize operating costs and it is often too late to achieve this.
The associations of engineers should recommend to the government that laws be legislated that offer tax incentives when designing Green buildings, because ultimately it is not only beneficial for who operates the building, but also for the country because it reduces the import of oil reducing the leakage of foreign currency and in the process protects the environment.
*About the author
Engineer Alfredo Sotolongo, president of Protec, Inc., is certified as a professional engineer in Puerto Rico and the State of Florida; has more than 40 years of experience in the application and sale of systems and equipment for energy conservation. He is a member of ASME (American Society of Mechanical Engineers), AEE (Association of Energy Engineers), with whom he is certified as an Engineer in Energy Management; he is also a member of ASHRAE and was president of the Miami chapter of that association. He has also presented numerous talks on the subject of energy conservation.
