The Auckland Harbour Bridge is made up of a lot of steel (Photo: Brendon O’Hagan).
The Auckland Harbour Bridge is made up of a lot of steel (Photo: Brendon O’Hagan).

The BulletinMarch 27, 2018

Joining the dots on the humble LED: the tiny tech that could change the future

The Auckland Harbour Bridge is made up of a lot of steel (Photo: Brendon O’Hagan).
The Auckland Harbour Bridge is made up of a lot of steel (Photo: Brendon O’Hagan).

Vector’s new technology engineer Kate Murphy shines a light on the history and impact little things can make on energy reduction at scale.

New inventions or refinements of old ones continue to make our life better, or at least easier. That’s not a bombshell. But what is sometimes not understood is how tasks that once took many days of work – if they were even possible – have become so easy we take them for granted.

The computer which flew the first astronauts to the moon – and, crucially, back again – had the computing power of your average 1980s pocket calculator. A modern smartphone has, by one estimate, 130,000 the processing speed of the poor old Apollo system.

And there are dozens of other examples, like the memory available on our devices, compared to early PCs, or the amount of data generated world-wide to fill those devices. If every person on Earth logged on to Twitter and tweeted continually for a century, it would produce 1 Zettabyte of data. In 2011, 1.8 Zettabytes was generated worldwide. And that’s before Donald Trump really hit his stride.

Another example is lighting the darkness. In ancient Babylon, the locals cracked a way of getting light without relying on hours and hours of cutting down firewood. The amazing breakthrough of sesame oil lamps required a day’s labour to buy 10 minutes of evening light.

For a long time, the technological advance was merely in the stuff being burned – animal fat, beeswax, the oil from the head cavities of sperm whales.

Kerosene, developed from the 1850s onwards, got you five hours of light for your day’s work. And helped save the sperm whale from extinction.

Then the electric light came along and completely revolutionised light. With the first carbon filament light bulbs, a day’s work could get you 762 hours, by the 1920s it was up to 3400 hours, and by the mid-1990s, a standard light bulb got you 20,000 hours of light for a day’s work.

Two-and-a-bit years’ light for a single day’s work. The massive improvement is due to limiting the energy wasted in heating things you actually want to light.

All forms of lighting, from wood fires to filament bulbs, relied on creating lots of heat to generate some light. Incandescent lightbulbs lose 90% of their energy to heat. Fluorescent bulbs, which have now largely displaced the old-school lightbulb, lose just 15%.

And lighting is in the process of being transformed again. Behold, the humble Light Emitting Diode (or LED for short).

They have been around as a technology for decades, and have become more efficient, brighter and lower cost by the year. Today, we have barely scratched the surface of their potential.

This underrated invention loses just 10% of its energy to heat, is five times brighter per watt than an incandescent light bulb, and lasts 25 times longer. Oh, and one light can be programmed to deliver a mind-boggling array of colours.

This means not just that LEDs are much more efficient to run, but that you can do lots of different things with them. Like, for instance, put them into groups, and strap the groups onto the side of some large structure, and treat them like pixels on a screen, making complex moving images by changing the tone and colour of each light.

A bit like this:


From a distance, the whole bridge appears lit – visible from many kilometres away. But up close, clusters of dots the size of your pinky fingernail are producing that light. There are in fact 2.8km of LED pixels, 96,376 of them in all.

To get an idea of where we’ve come, it’s worth trying to imagine retrofitting old technology in place of new. If Vector Lights consisted of 96,376 filament lightbulbs, as well as giving off a disconcerting warmth on the driver’s side every time you crossed the Harbour Bridge, it would burn five times as much energy. To light the bridge with old-school light bulbs would’ve required 1240 solar panels – compared with 240 currently – which would require the equivalent of over 100 household rooftops to accommodate. And that would not even cover the street lighting on the bridge.

“Ah, but Kate,” I hear you say for the sake of narrative effect, “LEDs are more expensive, and the cost savings don’t stack up.”

Well, as each improvement to LED technology is made, the price performance (the amount of light you get for your dollar) keeps improving. By one estimate, in the US, home LEDs provided 15 times as much light per dollar between 2008 and 2014. US consumers responded by installing nearly 80 million in their homes. By contrast, at the same time just 2% of homes were estimated to have LEDs.

LEDs price performance is increasing exponentially, as are the numbers being installed. Screengrab:

The cost savings to individual homes may be small, but the cumulative effect nationally is potentially profound, and LEDs are predicted to be among the fasted adopted technologies of all time.

If the 2013 census hasn’t lied to me (and why would it when it was filled out on old-fashioned paper after all), there are around 1.6 million homes in New Zealand, meaning there are roughly 37 million light fittings in homes up and down this land.

About one-third of these are in Vector’s Auckland-based network. If all these converted from compact fluorescent and incandescent bulbs to LEDs, the power saving would be like removing 80,000 homes from the grid at peak time. That’s equivalent to one-and-a-bit Hamilton’s coming off the grid. Or enough spare energy to charge 29,000 EVs.


At a grid level, that makes the current government’s goal of 100% renewable energy by 2030 that little bit more possible. At a home level, that frees up power for other uses, which makes the possibility of going ‘off-grid’ more achievable.

And that is a moral of this story. Distributed energy – where homes and businesses create their own power – is the way of the future.

Technology to enable energy trading and sharing between users is improving fast, so going off grid could be replaced by becoming an energy user and seller. Improvements in solar panels, battery storage and peer-to-peer trading platforms are all enabling this, but it’s also the little things which will make it more viable, more attractive, more normal, and will help get mass-adoption over the line.

The little dot, the size of your pinky fingernail, can be mighty.

This content is brought to you by Vector. If you live in Auckland, they also delivered the power you’re using to read it. And they’re creating a new energy future for all of us, as showcased by the incredible Vector Lights.

Keep going!