As the United States and other countries look to conserve energy within their power grid, there are many facts that must be understood as well as energy-saving ideas that pertain to building the next generation power infrastructure.
There is definitely a projected increase in the use of energy for both commercial and residential buildings. Quoting the United States’ NREL (National Renewable Energy Laboratory) website: “According to the U.S. Energy Information Agency, homes and commercial buildings use 71 per cent of the electricity in the United States and this number will rise to 75 per cent by 2025.”
Because there is a projection for more demand for power, some are proposing ways to lower those demands by implementing smarter systems that use various techniques to manage the power load. Some projected return on investments (ROI) for extra controls do not warrant their use in buildings.
Everyone talks about creating a better building environment and using less energy within commercial buildings, but integrating building automation systems (BAS) has not been as successful as many would want it to be. Also, some of the electrical solutions being proposed don’t have a realistic payback. In addition, some people are discussing efficiency but what about increased reliability and redundancy?
Switching versus dimming
The energy industry as a whole is migrating away from analog switching to digital switching. More buildings and other spaces requiring lighting for not only rooms within office space, but also conference halls and parking lots are looking for new solutions that also bring about energy conservation.
The cost to provide lighting per square foot is about $.45 (USD) for office buildings. Like any rule-of-thumb, that number depends on the tenant mix as well as the location of the building.
With all of the sophisticated automated dimming systems out there, you would think that adding these systems is the supreme way of designing lighting for buildings but in reality it is more about use of simple switching to facilitate cost savings.
A simple change of the way light fixtures are designed can help in providing more efficient lighting in spaces where 100 per cent lighting is not necessary all the time it is occupied. If this represents the overhead lighting fixtures within your room:
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Traditional Approach
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| Light |
Light |
Light |
Light |
Light |
| Light |
Light |
Light |
Light |
Light |
|
| Bank 1 |
| Light |
Light |
Light |
Light |
Light |
| Light |
Light |
Light |
Light |
Light |
|
| Bank 2 |
LIGHTING DESIGN – Each overhead bank of lights has one control for both rows. Either they are all ON or all OFF.
New designs are leading to better power efficiencies and local (occupant) control:
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New Approach
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| Light |
Light |
Light |
Light |
Light |
| Light |
Light |
Light |
Light |
Light |
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| Bank 1 |
| Light |
Light |
Light |
Light |
Light |
| Light |
Light |
Light |
Light |
Light |
|
| Bank 2 |
LIGHTING DESIGN – Each bank of lights has one control for EACH row giving the ability to turn off 50 per cent of the lighting in each bank and still have an even lighting across the space.
Give the occupant local control and override. This will actually provide some measureable results and be very cost effective. You cannot improve on anything until you measure and determine the base line usage and then make improvements from that starting point and compare results.
Insuring performance and delivery of savings
Expanding system’s requirements where they are more clearly defined upfront before any systems are implemented is one of the first steps to insure a bettering of overall systems performance and energy savings.
Another step is to make sure that the system is properly tested out prior to occupancy, so that it performs the way it was designed. Once an energy management system has been put in place and has been in use for several years, it is important to re-test it to see if it is still delivering those benefits that it was sold with or if other contributing factors have cut down its performance and power-saving capabilities. Contributing factors can be anything ranging from new users wanting different capabilities to some users “short circuiting” the system.
Sophisticated systems may save some money on power consumption but if the payback period is longer than two, three or even five years, many building owners and developers may opt out of paying extra for that savings.
A simple switch enabling you to cut back on 50 per cent of the energy to light a space may be a much more effective capability with an almost immediate payback compared to some automated dimming system with very expensive sensors that can be defeated by someone covering them with a piece of paper and forcing the sensors to sense “darkness” and turn the lights on at 100 per cent.
Saving energy costs is important but the cost of control is important as well.
CARLINI-ISM: Those energy management systems that have a 30 to 42 year payback will not sell to real estate owners looking for a realistic payback on Energy Savings initiatives.
Email the writer:
j.carlini@alrroya.com
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