Street lighting outside the University of London Observatory in Mill Hill

MQT on 2014-10-22
Session date: 
October 22, 2014
Question By: 
Andrew Dismore
Labour Group
Asked Of: 
The Mayor


The new LED lighting being introduced by TfL is  being  implemented in the vicinity of the Observatory without consultation and, more importantly, without any steps to ameliorate the potential impact of light pollution from the new street lights  on  the Observatory's work . At the end of last year, a single new LED lamp standard (which they  understand to be a "master" lamp, intended to act as a control node for future lamps) was installed near the Observatory.   That lamp, unlike the unit it replaced, has no internal baffles, no external shielding, and produces direct glare onto the  site, with a broad-band spectrum. The Observatory has tried to work with TfL but has now received a response which clearly implies that no further action is planned - not even installing shielding on the new lamp to remove the direct glare from which  they  now suffer. Will you visit the Observatory with me yourself, to see both the extraordinary and internationally recognised research work they do (and in relation to their recent discovery of a super nova you complimented them), the impact of light pollution form which they now suffer; and ensure that action  is taken  as with the previous lighting to reduce the impact of this pollution on their work?


Answer for Street lighting outside the University of London Observatory in Mill Hill

Answer for Street lighting outside the University of London Observatory in Mill Hill

Answered By: 
The Mayor

Renewal of the street lights along the A1 forms an integral part of my strategy to improve energy efficiency, reduce greenhouse gas emissions and lower electricity bills.  In the vicinity of the observatory the old street lights contain large, high wattage discharge lamps, the light from which is relatively difficult to control, so shields were installed to reduce stray light from interfering with the work of the observatory.  The replacement LED lighting, by comparison will have very small light sources, making optical control easier and resulting in their having the lowest glare rating of any highway lighting.  The advanced optical design of these street lights means that the addition of baffles would bring negligible additional benefit, however, TfL will be fully considering the need to minimise light 'spill' from the street lights to the surrounding area when carrying out the detailed design for lighting in the area.

Officers and lighting designers on behalf of TfL did meet with Professor Ian Howarth at the observatory in March so as to better understand his concerns.  Rest assured he will be advised of the detailed design proposal prior to new lighting being installed. In addition, TfL is installing a Central Management System (CMS) for street lighting which will allow lighting levels to be profiled appropriate to external factors e.g. traffic conditions, another means by which lighting levels can be controlled, at different times of the day.