Lighting in Design

LiD

FEB/MAR 2016

It’s difficult to see this as being a low-cost solution

and, given the research into LEDs, even as efficiency

increases in this process, so will that for LEDs.

Yet … yet, there is the emission spectrum that

comes from incandescent lighting that is still un-

matched by either fluorescents or LEDs. Museums

and galleries still prefer the colour presentation of

incandescents. And many people are terrified of the

mercury in CFL bulbs (which you’d only be exposed

to if you broke the damn things … but this does

happen).

One of the more tricky problems, though, is that

EU legislation has banned incandescents rather

specifically. Many countries have legislated for a

specific efficiency level (such as 15 lumens perWatt,

in Australia) which would suit the MIT prototype just

fine (at about 45 lumens perWatt, with a theoretical

limit of 272 lumens per Watt).

“LEDs are great things, and people should be

buying them,” says Solja

in MIT News. “But under-

standing these basic properties about the way light,

heat, and matter interact and how the light’s energy

can be more efficiently harnessed is very important

to a wide variety of things.”

The question is: what things?

At the moment the limiting factor for widespread

LED adoption is simply cost. Compact fluorescents

are cheap and long-lasting (and legally mandated over

incandescent lamps).The colour balance is gradually

being improved.

And LEDs are getting cheaper and better. Prob-

ably far sooner than these reabsorptive (vampiric?

what name should we use?) incandescent lamps will

become sufficiently cheap to use.

However, there is a market. Much as my wife

loves the look and feel of the squirrel cage incandes-

cent lamps that hang in our home, people still love

the physicality of seeing a real filament inside a real

glass enclosure.

Light isn’t only about luminance; it’s about the

feel of a venue and the expression of personality.

Plumen, a British company, specialises in pro-

ducing designer low energy lamps, including its

signature interlocking looped CFLs. It has created

an artistic LED lamp as well.

All of these are attempts to add warmth and

emotion to something that almost seems wired into

our biology. Not for nothing is the symbol of hav-

ing a sudden spark of inspiration the incandescent

lamp. There will be a market for these proper, more

efficient incandescents.

And, with a glance to my teacher, I can see I have

finally delivered. Let a million lamps lume.

A proof-of-concept device built by MIT researchers

demonstrates the principle of a two-stage process to

make incandescent bulbs more efficient.This device

already achieves efficiency comparable to some

compact fluorescent and LED bulbs. Image: Courtesy

of the researchers (MIT).

A schematic diagram of a new type of filter that could

revive incandescent lighting and make possible more

efficient solar electricity generation. The schematic

shows the technology from a front and side view (Purdue

University-MIT Image/Peter Bermel).

Front view

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