Return of the Standards War?

Four reasons for considering low voltage power in residential applications: to conserve money, to conserve power, to conserve resources, and to promote human wellbeing.

By David K. Warfel

I thought low voltage lighting was the future of residential lighting.

Then I looked into the future of lighting, and my head is still reeling from the shock. Absolutely everything about residential lighting systems could change, today, if we decide as an industry to make it happen.

And I mean EVERYTHING.

Power could be generated on-site. Smarter digital power micro-grids could reduce material usage while increasing efficiency. Fixtures could be simpler and smarter at the same time to guarantee interoperability and longer useful life. And all this could be delivered to the average home, instead of being exclusive to the world’s most wealthy individuals, through cost-saving overlapping technologies.

If this sounds too good to be true, that is because we are not particularly good at collaborating for mutual benefit when money is involved. Yet, there are many good reasons to work together to make this future happen now.

Resource Conservation

If you want to save the planet, reducing material waste just makes sense. Low voltage lighting power distribution could reduce the copper volume in a typical home by sixty percent. And copper is only the beginning of resource conservation; larger remote DC power supplies can improve efficiency over multiple smaller units, requiring less electricity.

Human Wellness

A redeveloped low-voltage lighting infrastructure could make it easier to deliver color tunable light to our homes and therefore easier to live every day with the benefits. Futuristic intelligent power systems are also safer by design – imagine a system where GFIs are no longer needed because the power itself knows when there is trouble.

Financial Equity

Rethinking the AC/DC debate and line voltage distribution of lighting power in our homes may also help us reduce the experience gap between those at the top and bottom of our economic system. Imagine taking the dollars currently spent on unused copper and investing them instead in better fixtures in production-built homes. That would lift the experience for everyone for generations to come.

How do we get to this fantastical future? We change our fixtures, our control technologies, and the very wiring infrastructure that powers it all. I wrote about potential fixture changes in the October issue of designing lighting (dl); I will tackle controls in the near future. In this issue, I invite you to reconsider the most invisible of lighting components: power distribution.

The Low Voltage Rewind

Can anyone give me a valid reason why we need 120VAC infrastructure for a 14W DC LED putting out 1,000 lumens?

-Mike Teolis, President, Colorbeam Lighting

Low voltage LEDs do not need 120VAC power.

Low voltage lighting, or perhaps more accurately low voltage direct current power for lighting, has been slow to gain traction in the residential sector. But, the idea of redoing our residential power systems is not a new one. In fact, the future of lighting at home might be something we can trace all the way back to the origins of electric light.

After reading Graham Moore’s excellent novel "Last Days of Night" and the highly informative "AC/DC" by Tom McNichol, I settled comfortably into a belief that Edison was indeed a force of nature but not quite the spotless hero. His DC current failed to win the war, after all, and he seemed to be terrible at long-term business management.

But, lately, I have come to wonder if Edison was not wrong about DC power, but simply a century too far ahead. Edison championed electric cars a century before EVs became the hot item in transportation. And, while no one would accuse Edison of being an environmentalist, his quest for a domestic organic rubber source would fit today’s sensibilities quite well. Was he too far ahead with DC power?

We are still running high-voltage copper throughout the house, but almost universally converting the power down to the low voltage DC power required by LEDs. It is time to correct this disconnect.

Using line voltage power is akin to overbuilding a home’s foundation. All the extra concrete in the ground is wasted effort, money, and resources.

The Future of Power

Simply switching to low voltage lighting could allow us to put 160 fixtures on a single 20A circuit, but that only scratches the surface of the power revolution brewing under the radar. Digital power systems answer the age-old AC/DC debate by refusing to compromise, delivering the safety and convenience of low voltage direct current power with the extended distance and wattage capabilities of alternating current. I think of this new approach as a digital protocol for power, though only smarter folks can tell if that analogy is even close to accurate.

Digital power systems send electricity in packets, effectively allowing power to behave like AC or DC when needed. Imagine a single receptacle in the house: your teenager plugs in their phone, without a power cube, and the power itself knows that they need 5V of DC power. Later, you plug in a portable heater and the same outlet knows you need – and delivers – 120VAC. Your toddler sticks their finger into the receptacle and milliseconds later it shuts off, leaving the child unharmed. And, there is no trip to the basement electrical panel for a reset – the power system knows when the finger is removed, and the vacuum cleaner is plugged in. While digital power is still in its infancy, I wonder if it could be advanced rapidly with a little collective effort.

Low voltage power can also be run on the surface of walls in paint-over and mud-over flat cables, making retrofit easier. Add native intelligence to the micro-grid in your home, and you can seamlessly integrate with on-site renewable energy generation like solar and wind. Smarter systems also increase resilience capabilities, automatically sensing power-hungry devices and shutting them down during power disruption. Some smart systems today can shut down a receptacle when power switches to a generator or battery backup; digital power can leave the receptacle active for cell phone charging but refuse to run a vacuum. And smarter power systems serve as a backbone for smarter lighting fixtures that transform our experience.

Smarter Fixtures

I cannot possibly list all the pros and cons of low voltage lighting in a single article, and it will take others to fully explain what I am only beginning to grasp. But, I do know that smarter lighting is possible when we reconsider our power systems.

We all learned (sometimes painfully) that heat is the enemy of LEDs. DC-DC drivers produce much less heat than the AC-DC drivers most of our recessed downlights use today, which could help our LEDs last longer. Their much smaller size will also make it easier to retrofit solutions and to insulate fixtures well, further increasing the positive impacts of the change.

Smart low voltage power will also make it easier to handle control protocols. In today’s fixtures, LED boards are connected to an AC-DC converter and driver; control protocols live in the driver. Tomorrow’s fixtures could feature LED boards with built-in Bluetooth mesh radios, eliminating the large external driver and making control universal.

As I considered low voltage lighting and smart power distribution while writing this article, it became increasingly clear that this was not just a cool technology shift, but also an opportunity to make the world a better place. And that gets me up in the morning.

Better Light for All

There are many ways that lighting professionals can make the world a better place, but if we continue to specify proprietary systems nearly impossible to swap out, every spec is a long-term problem for the people we serve and the planet we call home. We need to rethink lighting from start to finish, including how we manage power distribution, before we are stuck with another million homes built with outdated infrastructure. And that is just the homes that will be built this month.

If we cooperate and develop a new universal standard of digital low voltage power distribution, interoperable downlights and fixtures, and simple intelligent controls, we can deliver better lighting at lower cost, reach more people, and reduce the environmental footprint of our industry. Everyone wins, including people who never change their lighting but breathe cleaner air as a result of our energy savings.

What can you do to help? Start asking questions. If you are a manufacturer, ask your engineering teams about digital power, wireless controls, and interoperability. If you are a specifier, ask the manufacturers if they can deliver the fixture with onboard control communication or DC-DC drivers. If you are on the installation side, start asking questions about the volume of copper being run through your projects and consider alternatives.

I believe light can help us live better lives, and that the way we do lighting at home today is not the way to get there. So, let’s change it. ■

Special thanks to:

Mike Teolis, President of Colorbeam Lighting

Derek Cowburn, CEO of LumenCache

Michael Johnson, Partner, Global Lighting & Controls

Michael Krupinsky, Vice President of Environmental Lights