Wireless Sensor and Actuator Networks for Lighting Energy ...

Annual energy consumption
= ( Number of ballast) ( Ballast power) ( Daily operating hours)
( Operating days per year)
(9.1)
= 15 98 14 260 = 5, 350,800 Wh year = 5, 350.8 kWh year
The prototyping costs for each component of the research system are
summarized in Table 9-1, as are the projected prices for both retrofitting and new
installation after mass production and if the technology has matured. The difference
between retrofitting and new installation is the requirement of dimmable ballasts.
Dimmable ballasts are not included as a part of the cost for new installations since
ballasts are inevitable for fluorescent lighting systems, and it is a trend to adopt
dimmable ballasts for daylight harvesting capabilities. Moreover, daylight responsive
capabilities have become mandatory for new constructions in some states’ code of
regulations such as the Energy Efficiency Standards of California, and dimmable
ballasts are part of the construction cost. Most of the off-the-shelf electronic
components have price quotes available for large quantities, however the future price of
dimming ballasts and motes must be determined by educated guesses. The ultimate
price of the wireless platforms used in these calculations was $10. In fact, researchers
and developers of the wireless platforms optimistically estimate the cost to be about $1
in the future.
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