Ask the Electrician: Lighting Watts and Lumens

Q: What is the difference between watts and lumens?

Daylight Savings has arrived and the days are shorter and darker. This time of year we are all spending more time inside and looking to our lighting to keep things bright and chase away the darkness.

As lighting technology has become more efficient there has been a shift in terminology that can leave many consumers at a loss when selecting new bulbs and fixtures. In the days of the incandescent bulb it was common to select and discuss lights by the watts (actually Watt Hours) but new LED bulbs are more likely to refer to a lumen rating for output. 

Watts: Measures of Usage

Skipping a full physics explanation, many of the modern terms used to describe power usage originated during the industrial revolution as the world started to define relationships between power and time/output. The term watt was named after Scottish inventor James Watt. (He also coined the term horsepower in an effort to describe the power created by his improved steam engines to the public.)

In simple terms a watt is simply a measure of power produced. For electric light bulbs the term watts is commonly used to describe watt-hours (Wh) or the amount of energy used to power the bulb for an hour.

Cost was important:

As indoor electricity became commonplace, the cost of electricity was significantly higher than today so it made sense to discuss lights in terms of the energy or costs incurred.

For the consumer in 1880, the cost to run a 100Wh bulb for an hour was the equivalent of 3 hours of work, whereas today it is only seconds of labor for the same hour. (Reference: Statista.com)

Lumens: Measures of Output

As modern lighting has become more efficient the terminology is changing to focus more on measures of output than power usage. Here enters the lumen. Instead of a measure of cost a lumen is a measure of output of visible light.  

LED lighting today us roughly 7 times more efficient than incandescent bulbs so manufacturer’s are shifting their focus and labeling bulbs to reflect the amount of light produced rather than energy consumed. In addition modern LED bulbs last longer than traditional incandescent bulbs.

LED bulbs are simply more efficient at producing light/lumens with the same watt usage than incandescent, halogen or CFL bulbs. An incandescent bulb produces about 12-18 lumens per watt while modern LED can range anywhere from 75-100 lumens per watt depending on manufacturer and quality of the technology. 

Determining Lumen Requirements:

A simple chart or online calculator may be the easiest way to determine lumen requirements if you are replacing a single bulb that you are satisfied with. For more detailed lighting projects or upgrades to overall design you may want to look at the purpose of the room and/or fixture.  

Factors like square footage, room or fixture purpose as well as color range of the light emitted can have a big impact on selecting a light fixture.

What’s Next:

Once you understand the basics of lumen output and have determined your needs it’s important to look at the color range and type of lighting you would like to have.  We will talk about that next - stay tuned!

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Ask the Electrician is a column we publish with our advertising partner WCHL/Chapelboro. In “Ask The Electrician,” Scott answers common questions about electrical work, from switches and outlets to safety issues and preventative maintenance. If you have a suggested question for us to answer – or need an electrician – please reach out to our office.

See the article on Chapelboro.com: Lighting Watts and Lumens

Ask the Electrician: Lighting Temperatures and Types

Q: What color temperature and what type of light should I get?

Lights and basic lighting design become even more crucial during the longer nights of winter. We have talked about lumens as the amount of light provided by different bulbs and fixtures but this is not the only factor in selecting lighting.

Color Temperature:

Most light fixtures and bulbs will include information about the color of the light emitted based on the Kelvin scale. Kelvin is a measurement of thermodynamic temperature. Visually, lower Kelvin ratings appear warmer and have a red/yellow tint while higher ratings appear cooler and have more blue. Lights with the same lumen output appear completely differently to our eye based on the Kelvin or color temperature. Most residential indoor lighting commonly ranges from 2500K-6500K.

The temperature of the light helps to define what the space is used for. In general lower/warmer temperatures as used in living spaces and bedrooms. Kitchens & bathrooms are often mid-range or daylight temperatures, while offices and workspaces like countertops benefit from cooler color ranges.

New LED light fixtures often have adjustable color range settings so homeowners can select the temperature that they prefer based on the space or use desired. Individual bulbs are often labeled as warm white, daylight or cool white and should provide a Kelvin rating as well. Combining the color temperature with the type or goal of the lighting fixture is key to making the most of spaces and rooms in your home.

Types of Lighting:

Lighting and interior design typically look at three main types of lighting for any given room or space; general lighting, accent lights and task lighting. The best lit rooms often combine two if not all three of these elements to create a rich and welcoming environment as well as the functionality of defined the purpose of a given room or space.

• General or Ambient Lighting is used to simply provide basic illumination to the space. It is often a lower level or baseline of needed light for the room and often the first to be turned on upon entering a room. Commonly these are ceiling fixtures, floor lamps or can lights.  As a rule, ambient lighting is often warmer/lower Kelvin range.

• Accent Lights do exactly that - they provide additional light and direct attention to a specific area or feature.  It could be artwork, a fireplace or to draw attention to the kitchen island.  Often these are wall sconces, pendants or up-lights that are closer to a neutral mid range or daylight Kelvin temperature.

• Task Lighting is often the brightest and provides extra light for workspaces and areas like offices, kitchens and bathroom vanities. These are often under cabinet lights, desk lamps, spotlights and other directed lights.  Task lighting is often a cooler, higher Kelvin rating.

Which is Best?

Lighting decisions are a huge matter of personal preference. Don’t be afraid to experiment! Even swapping out a few light bulbs for a warmer or cooler color or more/less lumens can have a huge impact on your home. Feel like that one corner is always a little dark? Redoing your office and need a better option for your workstation?  Consider adding an additional or different type light fixture. A different light, new bulbs or more defined type light fixture can really change a space.

Buying & Installing Fixtures:

A majority of our customer chose to purchase their own fixtures. There are a ton of options and selections to chose from across a wide range of price points.  Dynamic Electric can help you install any new fixtures or simply update older ones.

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Ask the Electrician is a column we publish with our advertising partner WCHL/Chapelboro. In “Ask The Electrician,” Scott answers common questions about electrical work, from switches and outlets to safety issues and preventative maintenance. If you have a suggested question for us to answer – or need an electrician – please reach out to our office.

See the article on Chapelboro.com: Lighting Temperatures and Types

Ask the Electrician: Chasing the Dark

Q: The shorter days of winter are upon us, what is the best way to light up the night and get more useable light outdoors?

We have just rolled back the clocks are are all adjusting to the shorter days and less hours of daylight. We often get asked about the best gain in useable lights outside without being a nuisance or adding light pollution to the neighborhood.

Dark Sky/ Responsible Lighting Considerations:

You may hear the term “Dark Sky” friendly or compatible when looking at outdoor lighting. This is in its simplest terms a consideration of the amount of excess light pollution created by random exterior lighting that impacts communities and especially semi-rural areas.

Be sure to consider the following five principles for any outdoor lighting at you home:

• Useful: Outdoor lights should have a clear purpose or intent.

• Targeted: Lights should be directed/focused only where needed.

• Controlled: Lights should only be active when being utilized, this cuts down on both unnecessary light pollution as well as saving energy.

• Low Levels when Possible:  Consider multiple smaller well placed pathway lights vs. a bright flood light, using the lowest light level to be effective for your goal will have a huge impact on your overall light pollution.

• Use Warmer Colors:  Lights with warmer or “softer” color range reduces the amount of shorter wave “blue-violet” lights and are less impactful on the night sky.

Make a plan:

There are a lot of newer technologies available for adding lights to create great outdoor spaces as well as simply chasing away the dark in your yard. Some time spent researching and planning for what your really want is the first step in adding new lights or replacing older systems.

Pathway Lights:

These can be easy to install low voltage systems or even solar powered and offer the ability to add many smaller lights with a very direct purpose. Creating light along a driveway or walkway is a natural invitation to follow along a given path or add a highlight to an outdoor feature like a patio or garden area.

Motion Detectors:

Motion detectors are nothing new but the technology behind them has improved immensely.  Modern motion detectors are often heat sensitive so have less false alarms (for small creatures like the neighbor’s cat etc.). They also have a better range of sensitivity so can be better directed to activate when needed.

Dimmable or Dual Level Flood/Spot Lights:

Many newer systems offer the ability to have dual levels or dimmable lights for traditional flood or spot light fixtures.  These are great for providing a low level of light (for maybe walking the trash out) or an on demand brighter option (for working in the yard after dark) with the same fixture. Depending on the fixture these can tie in nicely with lights that have a dusk to dawn feature using the lower light setting for dusk to dawn and an option for brighter lights when needed.

Remotes & Timers:

Depending on your existing fixture, you may be able to simply update an existing fixture with a remote control or a timer. When coupled with new LED bulb technology this is an easy way to “upgrade” existing fixtures for better usability and control. 

Buying fixtures:

There are endless lighting options available both at specialty lighting stores, big box stores and of course online.  Do a bit of research to make sure you are spending your money well. Like anything, cheapest isn’t always the best option.

• UL Listed: make sure anything you purchase is UL certified to meet the minimum safety standards. This is especially important when buying online.

• Be aware or wet/outdoor certifications for any lights that are outside or in potentially damp locations, even garages can be considered “damp” locations due to the changing humidity levels. These fixtures should normally be GFCI protected as well.

• Ask questions and be ready to describe your goals for new lighting systems, as electricians we may be able to make suggestions or offer alternatives you haven’t considered.

Almost all of our homes have some sort of outdoor lighting but frequently we simply accept what we already have. Upgrades to exterior lights can make a huge difference, especially in the darker months of the year. Ask if it is time to make some upgrades or add some value to your home to chase away the winter blues!

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Ask the Electrician is a column we publish with our advertising partner WCHL/Chapelboro. In “Ask The Electrician,” Scott answers common questions about electrical work, from switches and outlets to safety issues and preventative maintenance. If you have a suggested question for us to answer – or need an electrician – please reach out to our office.

See the article on Chapelboro.com: Chasing the Dark

Ask the Electrician: Lighting Up Outdoor Spaces

Q: Outdoor spaces and lighting? Low-Voltage Plans:

Summer is here and even with some COVID restrictions lifting we are all more aware of making use of outdoor spaces. Adding outdoor lighting is a great way to make yards, walkways, decks, yards or grill areas more inviting.  Sounds great but where do you start?

Improving your outdoor spaces can be as simple as some ‘stick in the ground’ solar lights from your neighborhood big box store to elaborate landscaping designs that highlight a great tree, to everything in between.

Solar lights are great, eco-friendly and available to everyone who has enough sunlight but low voltage systems offer a lot more options and reliability. Low voltage lights run a huge gamut from simple path lights that plug into an existing outdoor outlet to elaborate systems that are hardwired to a transformer. Newer LED bulb styles mean there are great options for flood or spot light bulbs that rival more expensive 120V fixtures. Automatic timers and motion sensors are widely available in low voltages.

Here are the things to consider for low voltage lighting:

Plan:

Think about your goal, do you want simple path lights to make the driveway bright or are you looking for larger accents to make the backyard more inviting? Are you looking at a plug-in system or do you need a transformer installed? Once you determine what you’re looking for, the other requirements/considerations will fall in line.

Location/Footprint:

Be sure your fixtures and wires will be out of the way of existing maintenance needs; weed-whackers, irrigation lines, high traffic areas etc. Is your plan linear or will you need a “hub” location? How long is the run or length of wiring?

Fixtures:

We like Volt Lighting products for quality & affordability or Kichler for fancier high quality installations but there are plenty of online or big box options. Pay attention to component quality like connectors (remember the connectors live underground and will get wet, frozen and stepped on) and if you want features like timers, motion detectors or multiple voltages.  Like everything, you get what you pay for but low voltage systems can be very affordable for most homes. Working with a single brand/system will result in less potential “compatibility issues”.

Voltage:

Often “low volt” systems provide voltages from 12-24 volts to accommodate different set ups. Make sure your transformer and fixtures are compatible to the voltage available. In general the length, number of fixtures and fixture style may determine what voltage is best. Additionally, upgrading the wires themselves can be another way to add voltage capacity and improve durability.

Trenching/Getting it Done:

Be sure to call 811 before you dig so you don’t cut any existing cable or phone lines. (These are often less than a foot underground.)  It’s a free service and they will mark existing utility lines with paint so you know where they are. Be sure to bury your lines at least 6” below the surface to meet NC Code Requirements.

Consider what types of digging tools you may need, many of us have rocky or hard soil. A few lights may be practical with a shovel/home tools but longer wire runs go faster with a trencher.

Surface mounting to decks, concrete or other hard surfaces can generally be done with a drill and correct fasteners and wires can be enclosed in conduit as needed, so don’t limit your plan to “underground only”.

Anyway you do it, with summer approaching upgrading your exteriors spaces will make the coming months more enjoyable and add value to you home. If you’re not feeling quite up for a full DIY project, or need components like an additional exterior outlet or a transformer installed, give us a call and we are happy to help.  If you don’t want to DIY, we can handle the entire project for you, starting with an estimate/discussion of your plan! Our trencher is ready to go!

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Ask the Electrician is a column we publish with our advertising partner WCHL/Chapelboro. In “Ask The Electrician,” Scott answers common questions about electrical work, from switches and outlets to safety issues and preventative maintenance. If you have a suggested question for us to answer – or need an electrician – please reach out to our office.

See the article on Chapelboro.com: Lighting Up Outdoor Spaces

How do I determine which new bulbs to buy if I am switching to CFL/ LED bulbs?

In general we recommend going to LED rather than CFL, LED has become more affordable and offers better longevity than CFL bulbs. There are now good looking LED bulbs available for almost any application even retro style “Edison” bulbs. There are a few older application or small bulbs that remain most appropriate for a Halogen or incandescent bulb, mostly small bulbs found in appliances; refrigerator bulb, range hoods, some low voltage track lighting etc., but otherwise try switching to LED as you replace household bulbs

Look for bulbs from a reliable manufacturer, big names like Phillips, GE, Halo and Lutron, these may cost a bit more but offer better quality than unknown brands. If they offer a warranty, check to see if it applies only to the diode or if it covers the ballast/drivers as well. 

Fixtures are rated for either dry, damp, or wet locations, the same goes for bulbs and it will lessen the lifespan of the bulb to put an indoor bulb in an outdoor fixture. In addition, be careful to read the label on your fixture or bulb to see if it's dimmable. CFL's and LED's can blink, buzz and have a shorter lifespan if they are installed on an older incandescent only dimmer. We recommend changing your dimmers to a Lutron brand "CL" type for all CFL's and LED's. Some specialty LED fixtures require an "ELV" dimmer which cost more because it is more effective at dimming LED's. 

Over time switching your bulbs to LED is a great way to conserve energy as well as spend a bit less time changing bulbs, even making the swap in your most frequently used lights can have an impact. 

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Which light bulbs should I switch for energy efficiency first?

Most people transition to newer LED or CFL bulbs on a gradual basis as old incandescent bulbs burn out.  Think about which lights are on most often in your home and start there. For many homes these are lights in the kitchen or living room. Another area that can provide some energy savings is outdoor lights especially if they are on all evening on a regular basis. 

The other area we recommend doing first are any fixtures that are hard to access or require a ladder, switching these to a longer lasting energy efficient bulb not only saves money but saves the hassle of changing them on a more frequent basis.

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Why do my new LED/CFL lightbulbs not last as long as the package says?

We hear complaints all the time about new “long life” bulbs needing to be replaced or burning our prematurely. A couple of factors come into play here:

First the claims made on packaging are often for a 3 hour per day usage. A bulb that claims a 10 year life may burn out much quicker if it is being used for a kitchen or living room light that is on most of the time. If the bulb is on for 8-9 hours a day then the manufacture would estimate a 3 year lifespan based on the number of hours. It is always an estimate at best and individual bulbs when combined with fixtures/especially older ones may not meet the average as determined under laboratory settings by the manufacturer.

A second factor is the cost/quality of the bulb. With CFL and LED technology being relatively new there is a wide range of quality vs cost as these bulbs become more accessible to the public at a relative price range.  Components other than the bulb itself may fail and cause the bulb to “blow”, with CFL this is commonly the ballast and with LED it is a driver, both these parts regulate voltage to the bulb and can be affected by heat, vibration or other external factors and become the weak link in the functioning of the bulb.

A third factor in overall bulb life is the condition of the fixture and working environment itself. This is often harder to determine but some older light fixtures may simply be harder on new lightbulb technologies. Older dimmers and touch sensitive lights may be incompatible with new energy efficient bulbs and cause bulbs to burn out or not respond correctly. Enclosed fixtures may allow newer bulbs to overheat. Another environmental culprit may be vibration and loose or insecure connection in the fixture itself, kids romping around in a playroom above the kitchen or a wild dance party upstairs may be shaking the light fixture below, better quality bulbs may be unaffected but cheaper bulbs may fail as a result. 

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