LED There Be GasFrom Victorian Ornate

Engineering

To Modern LED Illumination

…The Best Of Both

Jonathan Skill (AMEY) & Chris Angell (Pudsey Diamond Engineering Ltd)

Preserving Our Heritage

• Sheffield has undergone a major facelift

• Many of the original gas lanterns have gone and those that remain were largely in a sorry state

• The gas lamps remaining on the suburban streets of Sheffield are listed and under the protection of Historic England (formerly English Heritage)

• A few had been adopted by the local community, re-furbished and still burn gas

Preserving Our Heritage

• How to preserve the lanterns but ease the maintenance burden?

• LEDs have had bad press

• Gas is not eco-friendly and someone has to pay for it (and the regular cleaning and mantle replacement)

• The columns are not suitable for mains power

• If it could be done, the ideal solution would be to use solar power (free energy, clean and low maintenance) & LEDs, provided they could look as if they weren’t LEDs!!

Sewer Gas Destructor Lamps

Biogas forming in sewers via anaerobic digestion can be a potentially foul-smelling and explosive hazard. Unlike ordinary gas lanterns for street lighting, the main purpose of sewer gas destructor lamps was to remove sewer gases and their hazards. Joseph Edmund Webb of Birmingham patented a sewer gas destructor lamp in 1895. (Wikipedia)

These Lamps (not lanterns) were lit 24 hours a day, burning Town Gas to create heat (and a little light). The heat rising through the dome and chimney, drew “air” from the sewers below and safely burned excess methane and expelled it to the atmosphere.

Sewer Gas Destructor Lamps

Eighty-four of these street lamps were erected in Sheffield between 1914 and 1935, the largest number in any British town, due mainly to the many hills in the area where gas could be trapped. Sheffield on the Net - City Curiosities, via Wikipedia

Around 27 still exist, four of which still burn gas!

Preserving Our Heritage

Some installations were almost unrecognisable as Gas Lamps!

At 100 years old the original Gas Destructor Lamps are showing some wear and tear!

Preserving Our Heritage

In this example the original corroding metalwork has been painted to halt further deterioration

Preserving Our Heritage

• Project Remit:

• To Re-use as many mechanical elements as possible

• Any new mechanical parts to match old as closely as possible

• To convert the Gas Lamps to Solar-powered LED

• The overall Victorian Aesthetic to be preserved

At first glance (and possibly at closer inspection), the Gas Lamps should look as they did when first installed

Preservation and Modernisation

• Pudsey Diamond Engineering were contracted to return the gas lanterns to their original glory while bringing them into the 21st

Century

• We specialise in small-scale metal engineering – the mechanical refurbishment precisely aligns with our skill set

• We also design, in house, the electronics for illuminating and managing traffic bollards utilising solar power

• This was a project too interesting to pass up……

To Preserve or to Renew?

• The project remit was clear – reuse as many original parts as possible and when parts were missing or damaged, replace with identical new parts

When Parts Are Broken Or MissingBronze Finials Bronze Galleries and Cast Iron Platforms

All castings patterned on original parts

Spinnings..

Technique similar to Victorian, but now in Stainless Steel

Solar Gas Lamps?

• Pudsey Diamond has developed a solar-powered, illuminated, trans-reflective bollard for use where mains power is unavailable or where energy saving is of paramount importance.

• This technology has been utilised in the Sheffield Sewer Gas Lamp renovation

Why Solar?

• The Destructor Lamps have no access door because of the need to bring gases up from the sewer beneath. Bringing mains power into the column would require the column to be modified or replaced – neither option meets the requirement of preservation.

• Solar power can be provided from panels discreetly mounted within the lantern and the storage batteries are hidden beneath the solar panels

• Maintenance is low, power supply is free

Gas Mantles• The mantle is a roughly pear-shaped fabric bag, made from silk, ramie-

based artificial silk, or rayon. The fibres are impregnated with rare-earth metallic salts; when the mantle is heated in a flame, the fibres burn away and the metallic salts convert to solid oxides, forming a brittle ceramic shell in the shape of the original fabric.

• A mantle will glow brightly in the visible spectrum while emitting little infrared radiation (sound familiar?).

• The mantle aids the combustion process by keeping the flame small and contained inside itself at higher fuel flow rates than in a simple lamp. This concentration of combustion inside the mantle improves the transfer of heat from the flame to the mantle. The mantle shrinks after all the fabric material has burned away and becomes very fragile after its first use.

Extracts from Wikipedia

LEDs replace Gas• LEDs have a poor reputation for their “blueness” leading to problems for

wildlife, glare for drivers, sleep deprivation – a blue-biased gas lamp would not look right

• Gas lamps, before the invention of the mantle, were very yellow and produced little light

• The mantle produced a whiter light at just about the perfect colour temperature (2,700 to 2,800K)

• The LEDs chosen for this project are 2,700K almost precisely matching the light from a gas mantle

• Gas mantles produced light across their surface area which reduces the glare – LEDs in comparison are small point sources of high intensity light……………..

The Modern Mantle

• Not silk; resin-based plastic

• No exotic metal oxides• Performs the same

function• Very low IR emission• Soft white light output• LED colour temperature

matched to gas mantle

The Modern Mantle

UV Post Curing

In a converted Microwave Oven!!

Mantle Assembly With Solar Power

Sheffield’s Gas Lamps Brought Back…….

Before……

• The demise of this old lamp left this pathway dark until a modern LED column was installed.

• The re-furbished Gas Lamp provides the Victorian elegance once again (while leaving illumination to the modern fixture)

…...and after

…But That’s Not All….

• By utilising technology developed for bollards these “new” gas lamps have additional capabilities.

• Solaboll uses short range RF to provide remote control and management of it’s systems and functions….

• Using Databoll…

Remote Diagnostics• Databoll provides remote checking of battery voltage, solar panel

voltage, light sensor and temperature

• It also allows remote control of LED brightness, dusk & dawn light thresholds and other functions

• In addition, because Solaboll keeps a log of its battery voltages, Databoll can download this data for later analysis

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Re-use of Technology

• The Victorians built their devices to last

• We have re-furbished the gas lanterns, re-using Victorian technology as appropriate

• The 21st Century elements are also a re-use of technology – developed for bollards, now implemented in gas lanterns

• And the re-use goes on…..

New Lanterns From Old

• Building on the success of the Sheffield Gas Lanterns new designs are being developed with higher output for street illumination (mains powered)

• The mantles provide a soft, reduced glare light source

• New innovation offers “steerable” light from the mantle – allowing the street to be lit but not bedrooms

Jonathan Skill – AmeyChris Angell – Pudsey DiamondSheffield City CouncilHistoric England