Artificial lighting is a significant load on the electrical infrastructure. Traditionally, up to 30% of a building\u2019s electric load was used for lighting. The U.S. Energy Information Administration estimates that lighting takes up about 5% of the total electricity consumption in the United States. Generating electricity costs money, and each of the various forms of generation has some adverse impacts, such as pollution, nuclear waste, or affecting the wildlife we enjoy in nature.<\/p>\n
Since we spend so much time under artificial lighting, which costs so much to produce, we need to use our lighting resources wisely. For this reason, we have several codes regulating the use of lighting power. Those less familiar with the National Electrical Code<\/em> (NEC<\/em>) may be surprised to know that the NEC<\/em> does not<\/strong> set standards for energy usage. In fact, the purpose of the NEC<\/em> is \u201c\u2026the practical safeguarding of persons and property from hazards arising from the use of electricity.\u201d It also states, \u201cThis Code<\/em> is not intended as a design specification or an instruction manual for untrained persons.\u201d [NEC<\/em> 90.1(A)]<\/p>\n In other words, even when you have the NEC<\/em> mastered, we\u2014who work in and around the electrical trade\u2014still have more to consider when it comes to artificial lighting.<\/p>\n The NEC<\/em> does not address the question, \u201cHow much light is needed?\u201d The Illuminating Engineering Society (IES) is an organization that provides excellent lighting level guidelines for the various visual tasks we perform, including work, entertainment, and recreation. Lighting can be very utilitarian as it affects the safety and the ability to perform tasks properly, but it can also be used to set the mood for an area. Likewise, since appropriate illumination for one individual may not be adequate for another, lighting design becomes a blend of quantifiable science and a perceived artform. The North American chapter of the IES has many guidelines, and it does an excellent job of handling the myriad of factors that come into play in delivering proper glare-free lighting levels for use in various applications.<\/p>\n Article 220 of the NEC<\/em> provides some of the requirements for electric lightning.\u00a0 It addresses service load calculations, and Table 220.12 has unit load factors for lighting in various occupancy types. These loads help ensure sufficient electrical capacity to handle the potential lighting loads. However, the NEC<\/em> does not have standards that address energy conservation in lighting design.<\/p>\n Various states and municipalities have unique energy codes, but these are mostly based on three primary energy codes:<\/p>\n I mention the California energy code because it stands alone and does not simply reference one of the other two codes. Each code is on a three-year cycle and gets adopted by states and municipalities. They are all similar, with some exceptions, and all aim to set standards to save energy. The NEC<\/em> acknowledges these energy codes and allows the electrical system sizing to be adjusted based on the energy code followed [see NEC<\/em> 220.12(B), Lighting Load for Non-Dwelling Occupancies<\/em>.]<\/p>\n Each energy code allows the lighting designer to break the building down into its parts and provides appropriate Lighting Power Density (LPD) for those areas or allows the entire facility to be taken as a whole. Table 1 shows how the overall facility LPD values for these various codes compare.<\/p>\n The various codes explain how lighting needs to be controlled in multiple building areas and under specific circumstances. While the three main codes handle the controls in slightly different ways, there is significant similarity and overlap between the codes. Table 2<\/a> compares the codes and their approach to these controls.<\/p>\n Download Table 2<\/a><\/strong><\/p>\n With the guidelines from the energy codes, a lighting designer\u2019s next task is to decide how to meet those requirements. Simple lighting controls (toggle switches) started with line-voltage wiring, but low-voltage wiring methods became common as systems grew more advanced, including occupancy sensors, time clocks, and dimmers. As controls get more complex and wireless technologies advance, wireless lighting control options become increasingly appealing. It is also possible to purchase luminaires with built-in occupancy and daylight sensors. These sensors can control each luminaire separately or be networked to function together.<\/p>\n <\/p>\n <\/p>\n <\/p>\n <\/p>\n <\/p>\n <\/p>\n The essential components of lighting controls consist of the following:<\/p>\n Energy code adherence requires:<\/p>\n However, the result is energy\/cost savings that ultimately allow us to be wiser stewards of our natural resources. So, the next time you are up burning the midnight oil to meet that deadline, be grateful for the many innovations that allow us to comfortably and responsibly see the task at hand.<\/p>\n Several codes regulate the use of artificial lighting. Let\u2019s examine the requirements of the NEC, IES, and other standards.<\/p>\n","protected":false},"author":412,"featured_media":25150,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"footnotes":""},"categories":[23083,23260],"tags":[22753,23161,23141,23262],"class_list":{"0":"post-25147","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-electrical-fundamentals","8":"category-2022-november-december","9":"tag-holiday-lighting","10":"tag-lighting","11":"tag-lighting-and-controls","12":"tag-november-december-2022"},"_links":{"self":[{"href":"https:\/\/iaeimagazine.org\/wp-json\/wp\/v2\/posts\/25147","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/iaeimagazine.org\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/iaeimagazine.org\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/iaeimagazine.org\/wp-json\/wp\/v2\/users\/412"}],"replies":[{"embeddable":true,"href":"https:\/\/iaeimagazine.org\/wp-json\/wp\/v2\/comments?post=25147"}],"version-history":[{"count":3,"href":"https:\/\/iaeimagazine.org\/wp-json\/wp\/v2\/posts\/25147\/revisions"}],"predecessor-version":[{"id":25158,"href":"https:\/\/iaeimagazine.org\/wp-json\/wp\/v2\/posts\/25147\/revisions\/25158"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/iaeimagazine.org\/wp-json\/wp\/v2\/media\/25150"}],"wp:attachment":[{"href":"https:\/\/iaeimagazine.org\/wp-json\/wp\/v2\/media?parent=25147"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/iaeimagazine.org\/wp-json\/wp\/v2\/categories?post=25147"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/iaeimagazine.org\/wp-json\/wp\/v2\/tags?post=25147"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}How Much Light Do I Need?<\/h2>\n
![\"Photo](\"https:\/\/iaeimagazine.org\/wp-content\/uploads\/2022\/10\/2022-11-stevens-ph1.jpg\")
<\/a>What is Appropriate Energy Use for Lighting?<\/h2>\n
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<\/a>How Does the Lighting Need to be Controlled?<\/h2>\n
<\/a><\/a><\/a>
backup<\/figcaption><\/figure>\n<\/a>Typical Lighting Control Components<\/h2>\n
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Conclusion<\/h2>\n
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References and Helpful Links<\/h2>\n
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\nhttps:\/\/www.eia.gov\/<\/a><\/li>\n
\nhttps:\/\/www.darksky.org\/<\/a><\/li>\n
\nhttps:\/\/www.energy.ca.gov\/<\/a><\/li>\n