1

BLISS

Better Lighting in Sustainable Streets

Technical Case Study

Sankey Valley car park St.Helens, UK

TCS 5.1

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Contents

1.0 Background ……………………...………………………………………………………………………………………………….. 3

1.1 Site description

1.2 Crime considerations

1.3 Accident considerations

1.4 Social demographic considerations

2.0 Existing installation ………………………………………………………………………………………………………………. 4

3.0 Design development …………………………………………………………………………………………………………….. 5

4.0 Total Cost of Ownership ……………………………………………………………………………………………………….. 6

4.1 Initial capital expenditure

4.2 Energy provision

4.3 Maintenance strategy

4.4 Total Cost of Ownership 25-year expenditure

4.5 Payback Period

5.0 Design specification ……………………………………………………………………………………………………………... 7

6.0 Sustainability ………………………………………………………………………………………………………………………… 8

6.1 Energy

6.2 Materials

6.3 Obtrusive light considerations

7.0 Results …………………………………………………………………………………………………………………………………. 9

8.0 Conclusion …………………………………………………………………………………………………………………………... 10

Abbreviations and definitions .………………………………………………………………………………………………………...… 11

Key information Year 2011

Theme Sustainability

Scheme type Car park

Scheme location St.Helens, UK

Property type Visitor Centre

Size of car park Small (18 spaces)

Speed limit NA

Crime rate Low

Existing installation 70W High Pressure Sodium (at building only)

Main consideration New installation in wildlife sensitive area

New installation LED motion detection trial

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1.0 Background

The principal aim of the 2011 Sankey Valley car park

scheme was to provide lighting to encourage people to

use the site all year round, with careful consideration

to the local ecology. The scheme includes the

installation of 2 different LED luminaires which utilise

motion detection via passive infrared sensors, limiting

the amount of energy used.

1.1 Site description

Sankey Valley is a 7-mile linear park and trail

and the visitor centre is located in the

Blackbrook ward, 1.9 miles (3 km) from the

centre of St.Helens. The car park has an average width

of 20 metres and length of 47 metres. The visitor

centre is a small building of 9 metres by 11 metres in

size.

According to the Office for National Statistics (2011),

St.Helens has a population of 175,400, with Blackbrook

housing 10,700 people. Within a 1 mile (1.6 km) radius

of the estate there are a number of key services

including; a petrol station, schools, medical centres,

leisure centres, a supermarket and places of worship.

The visitor centre is situated behind a public house and

bound by a church, residential estates and one local

distributor road, leading onto the A580 connecting

St.Helens to Liverpool and Manchester.

The visitor centre has facilities for the public, including

toilets and is home to the rangers of the park who are

there to provide information regarding conservation

projects and walks starting from the car park. School

events including pond dipping and bug hunting can be

organised, as well as public events including guided

walks, bird watching and art days.

According to the 2001 Census 67% of households in the

area own one or more vehicles, and only 12% of people

use public transport to travel to work.

1.2 Crime considerations

There are no reported crimes at the car park

or the visitor centre in the 3 years prior to

the scheme installation, or 3 year after the

installation after consideration of the 5 crime types;

rowdy and inappropriate behaviour, criminal damage,

theft from a vehicle, theft of a vehicle and burglary

dwelling.1

1 Information obtained from Merseyside Police crime report data.

1.3 Accident considerations

Before (3 years): 0 accidents

After (3 years): 0 accidents

The accident statistics are based on reported accidents

during the hours of darkness on the car park. There are

no reported accidents before or after the scheme

installation.2

1.4 Social demographic considerations

The information below shows key social

economic data for the Lower Super Output

Area (LSOA) covering the area which helps to

develop a representation of the potential activity in the

hours of darkness.

Gender and age – Information obtained from the Office

for National Statistics (2011) shows that the gender

and age profiles are fairly evenly divided, with a slight

majority of people in the age range of 45-64 years.

Deprivation – The LSOA covering the area has an Index

of Multiple Deprivation (IMD) score of 9/10 (2010). A

score of 10 would indicate the LSOA is ranked among

the most deprived 10% in the country.3

2 Information obtained from Merseyside Police accident report data.

3 IMD 2010 score combines 7 domains of deprivation: Income,

employment, health and disability, education and training, barriers

to housing and services, living environment and crime.

Chart 1: Age

Chart 2: Gender

Age

65+ 17%

20%

26%

20%

17%45-64

30-44

16-29

0-15

54%46%

Gender

Female Male

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2.0 Existing installation

Table 1: Existing installation information

The existing luminaires were situated around the side

of the visitor centre and provided poor optical control.

There were no previous lighting units on the car park.

The existing lighting was maintained by the ranger

service and was provided to illuminate the front

entrance and pathway to the rear of the building

where the car park included 7 public car parking

spaces.

Plan 1: Sankey Valley car park existing scheme

The existing installation was identified as being

inefficient with respect to:

� Poor colour rendering properties of the HPS lamps

� Deteriorating lumen output

� Increased number of reactive maintenance visits

� High energy consumption

� UV content of the lamps

The installed luminaires were equipped with low loss

electro-magnetic control gear, and switched via

electronic standard photo-cells with a 70/35 lux

switching regime (4,147 annual burning hours).

Image 1: Sankey Valley car park existing scheme

Image 2: Sankey Valley car park existing scheme detail

Image 3: Sankey Valley car park trail entrance

No. Age Column type Luminaire Arrangement Light source &

wattage

Colour

temperature

(K)

CRI

(Ra)

Efficacy

(lm/w)

Energy

consumption

4 11

years

4m steel,

post top

mounted

Square deep

bowl

Around side

of visitor

centre only

70W HPS 2000K

Warm white 20 100 lm/w

1,443 kWh,

750 Kgs

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3.0 Design development

Selection of the appropriate lighting classification;

Criteria Factor Description

Road type Outdoor car

park

Surface car parks. One entrance/ exit. Entrance to Sankey Valley linear park

and trail situated in car park.

Traffic flow Light traffic Parking areas of shops, terraced and apartment houses: cycle parks.

Located adjacent to distributor road and behind a public house.

Crime rate NA No crime recorded for the area prior to scheme installation. No monitoring by

any local authority CCTV surveillance equipment present.

Colour rendition Ra ≥ 60

Ra ≥ 60 chosen as appropriate for the use of LED luminaries in the new

scheme.

Environmental

zone E2/ E3

Location lies on the edge of 2 zones. Rural; Low district brightness. Village or

relatively dark outer suburban locations.

Medium district brightness; Small town centres or suburban locations.

Safe ease of

passage Moderate

Pedestrian ease of passage moderate; Small car park, pedestrian footfall

medium, footpaths to country park, vegetation surrounding majority of car

park, general visibility good.

Design

uniformity

Uo high as

possible

Overall uniformity of illuminance (Uo) should be as high as possible with

consideration to financial and environmental implications.

Control method PIR motion

detection

Passive Infrared control on 9 of 11 new LED luminaires; Low traffic flow,

especially during the hours of darkness, low crime rate, colour rendering

index ≥ 60.

Electricity

supply

Private

Network

Cable

DNO low voltage system supply located within feeder pillar near visitor centre,

private cable supplied existing 4 columns, but not continuous throughout the

site. New cabling required to ensure an optimum design solution.

Table 2: Primary and secondary design factors

The following design standards were utilised within the

design process in 2011;

� BS EN 13201: 2003 Road Lighting

� BS 5489: 2003 Code of Practice for the design of

road lighting

With consideration to the criteria above, an S4 lighting

classification of 5 lux average was chosen to provide an

appropriate level of illumination as identified in table 3.

As an energy consideration, 9 of the 11 luminaires are

operated by a PIR system which operates when motion

is detected and stays on for as long as motion is

present. If no motion is detected after 5 minutes, the

lighting reduces to 10% of full light output, then

switches off completely shortly afterwards.

Table 3: Selected lighting classifications

According to BS 5489: 2003 Code of Practice for the

design of road lighting;

For subsidiary roads…the lighting class can be varied

when a light source with a higher Ra value is used.

This suggests that an S5 lighting classification could be

utilised at full brightness. However, as part of the

design development, a risk assessment was undertaken

and the decision was made to control the majority of

the luminaires via PIR, with two controlled via

photocells operating on a normal street lighting regime

to provide a suitable lighting level at times of lower

activity in the area.

Each luminaire fitted with PIR motion detection is

programmed individually and is adjusted via the

manufacturers’ commissioning engineer.

Class

Horizontal Illuminance

E in lx

[minimum maintained]

Emin in lx

[maintained]

S4 5.00 1.00

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4.0 Total Cost of Ownership

To support the lighting design process, a 25-year Total

Cost of Ownership evaluation was undertaken to

determine the cost effectiveness of each design option.

The evaluation is based on the installation of

luminaires only, on the opinion that the replacement of

inefficient lighting columns would be included during

routine maintenance operations.

4.1 Initial capital expenditure

One element was considered:

• Supply and installation of the equipment

(luminaire, lamp and control)

Table 4: Initial capital expenditure

4.2 Energy provision

The energy provision was calculated using a cost per

kWh based on Estimated Annual Consumption at

commission year, excluding inflation and taxation:

• Energy cost per kWh: £0.105p

• Regime: Switch on 70 lux / switch off 35 lux

• Burning hours: 4,147 per year (11.3 per day)

• 50% occupancy on all options4

• Carbon: 0.52 Kgs per kWh

• Previous energy consumption and annual cost:

1,443 kWh £152

Table 5: Energy provision

4.3 Maintenance strategy

Planned maintenance regimes were considered; cyclic

activities of lamp replacements, luminaire cleaning,

structural inspections and electrical testing.

4 Based on the LED manufacturers’ assumptions of a PIR burning

hours of 50% compared to a traditional scheme when conducting a

TCO of Folio LED.

A four year cyclic maintenance programme was applied

to the HPS and CPO options. The LED luminaires have a

predicted longer life, therefore no additional LED

module replacement cost was included in the

evaluation.

• Previous annual maintenance cost:

4no. £15 (£3.75 per column)

Table 6: Maintenance operations

4.4 Total Cost of Ownership 25-year expenditure

Table 7 outlines the total predicted expenditure over a

25-year life cycle.

Table 7: TCO 25-year expenditure

4.5 Payback Period

Table 8 outlines the estimated period of time to

recover the initial capital expenditure through annual

energy and maintenance savings.

Table 8: Payback Period

The results indicate that an LED scheme is the most

cost effective solution over a 25-year period and has

the shortest payback period.

The LED scheme has high initial capital costs; however

the energy and maintenance costs are significantly

reduced compared to a conventional scheme. An LED

scheme has the potential to reduce maintenance visits,

resulting in environmental gains for a more sustainable

solution.

5 Based on energy savings only. Increase in maintenance costs added

to capital costs.

Option No. Capital cost

HPS: 50W 11 £2,694

CPO: 45W 11 £3,015

Final design LED

50% occupancy 11 £5,838

Option No. Energy %

saving

Annual

cost

HPS: 50W 11 1,483 kWh

771 Kgs -3% £156

CPO: 45W 11 1,348 kWh

701 Kgs 7% £142

Final design LED

50% occupancy 11

952 kWh

495 Kgs 34% £100

Option No. Annual cost

per luminaire

Annual cost

per scheme

HPS: 50W 11 £2.80 £31

CPO: 45W 11 £9.76 £107

Final design LED

50% occupancy 11 £1.12 £12

Option

Initial

capital

cost

Energy &

maintenance cost

Whole

life cost

HPS: 50W £2,694 £4,670 £7,364

CPO: 45W £3,015 £6,234 £9,249

Final design LED

50% occupancy £5,838 £2,808 £8,646

Option

Initial

capital

cost

Annual energy &

maintenance

savings

Payback

Period

HPS: 50W £2,694 -£20 NA

CPO: 45W £3,107 £105 311 years

Final design LED

50% occupancy £5,838 £55 106 years

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5.0 Design specification

Plan 2: Detailed design specification

The Sankey Valley car park scheme utilised one

manufacturers’ LED luminaires, approved following an

initial product evaluation exercise. The luminaires have

different aesthetic qualities from traditional, to the

specific Folio leaf shape design.

9 of the 11 luminaires include PIR motion sensors

which operate when motion is detected. If no motion is

detected after a five minute period, the lighting

reduces to 10% of full light output, then switch off

shortly afterwards. Two of the lanterns operate on a

regular street lighting switching regime of 70/35 lux

switching regime (4,147 annual burning hours).

Image 4: Sankey Valley car park new scheme day

Image 5: Sankey Valley car park new scheme Folio

Image 6: Sankey Valley car park new scheme Realta

Thorlux Folio 18 LED 38W lanterns with motion detection

Lanterns 5 - 9

6000K Cool white

Thorlux Folio 18 LED 38W lanterns with

dusk – dawn switching Lanterns 10 & 11

6000K Cool white

Thorlux Realta 18W LED lanterns with motion detection

Lanterns 1 - 4

5000K Cool white

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6.0 Sustainability

6.1 Energy

Energy profiles were calculated based on

manufacturers’ UMS6 technical data to

ensure that the new installation achieved a

significant energy reduction, in accordance with the

BLISS project aims.

Installed power (Watts)

Before 344W

After 360W

Savings (%) -16W (-4%)

Table 9: Installed power

Calculated annual energy consumption,

C02 emissions and savings (kWh, Kg C02)

Before 1,443 kWh 750 Kgs

After 952 kWh 495 Kgs

Savings (%) 491 kWh (34%) 255 Kgs (34%)

Table 10: Energy consumption

Compared to installed watts identified in table 9,

annual energy savings are achieved with the use of

efficient electronic control gear, including the use of

motion detection as identified in the calculated

consumption figures in table 10.

Image 7: New scheme with no motion detected

6 Information calculated using ELEXON Unmetered Supply charge

code and switch regime information.

6.2 Materials

The luminaire housings are made from

aluminium with glass bowl protectors,

which are both highly recyclable. The

manufacturer selected enforces WEEE (Waste Electrical

and Electronic Equipment) charges to recycle their

products.

LEDs have a predicted longer life than other

lamps and do not produce UV light that can

have adverse effects on the local ecology.

6.3 Obtrusive light considerations

The environmental zones E2 rural/ E3

medium district brightness, were selected for the car

park. Specific criteria from the ILP (2011)

guidance note relating to obtrusive light considerations

for the E3 classification were utilised, and E2 where

appropriate, during the equipment selection process.

The selected luminaires incorporate a flat glass design

and specify an Upward Light Output Ratio (ULOR) of

<3.5% of luminaire flux, limiting the amount of light

spill and glare. LEDs are a very directional light source

and produce minimal upward light, reducing the

contribution to obtrusive light and sky glow. LEDs do

not produce UV light that can have adverse effects on

the local ecology.

Image 8: New scheme with motion detected

34% Energy savings

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7.0 Results

Table 11: Results

Comments on the new scheme where received from a

local Countryside Development Officer;

The installation of movement sensitive/ energy

efficient lighting at the Stanley Bank Visitor Centre has

had a significantly beneficial effect on the effectiveness

and usability of the building. Prior to the

improvements, at night time and on winter evenings,

the centre car park was poorly lit with inefficient

lighting equipment and attracted anti-social behaviour.

The installation of motion sensitive energy efficient

lighting has made the car park feel safer, allowed

better community use of the centre, vastly reduced

anti-social behaviour including fly tipping, and reduced

the impact of lighting on wildlife at this important Local

Nature Reserve.

The installation achieves an estimated reduction in

energy consumption compared to a traditional scheme,

and utilises LED luminaires which reduce adverse

effects on the local wildlife. The scheme also achieved

an improvement in colour temperature, colour

rendition and provides uniform overall illumination

across the previously unlit car park area.

Before After Outcome

Calculated

energy

1,143 kWh

750 Kgs of CO2

952 kWh

495 Kgs of CO2

34% energy

saving

Number of

luminaires

4no.;

70W HPS

11no.;

4no. 18W LED

7no.38W LED

Increased

units

Calculated

colour

rendition

Ra ≤ 20 Ra 65

Improved

colour

rendition

Calculated

colour

temperature

2000K

Warm white

5000K– 6000K

Cool white

Improved

appearance

Control

regime None

PIR motion detection

(9 of 11 luminaires)

Improved

functionality

Public

consultation

research

None

None NA

Measured

crime 0 0

Unaffected

crime

Measured

accidents 0 0

Unaffected

accidents

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8.0 Conclusion

The primary objective of the Sankey Valley car park

scheme was to provide new lighting and encourage

more people to use the park, without having any

adverse effects on the local ecology. All performance

aspects of the new luminaires as detailed in section 8.0

performed well, including estimated energy savings of

at least 34%, improved colour rendition and high

lighting levels.

The scheme aimed to create an environment that

encouraged people to visit the area with increased

feelings of safety, and records indicate that no crime

incidents have been recorded following the scheme

installation.

Comments from a local Countryside Development

Officer suggest that the lighting has had ‘a significantly

beneficial effect on the effectiveness and usability of

the building’ also the use of motion detection has

‘made the car park feel safer’.

The choice of modern luminaires and columns where

secondary to the choice of technology, however they

are a sleek and sensitive design for the built up

woodland area.

The use of motion detection is one way to ensure the

lighting is only operational when needed. However

issues were raised during the design process regarding

sensitivity of the PIR sensors, with regard to sensor

triggers, for example trees branches or small animals.

This issue is being monitored and actions can be taken

to reduce false triggering including reducing the

sensitivity of the PIR, or to disable the PIR in a specific

problem luminaire.

The success of this scheme will influence the future

lighting strategy for car parks, and especially for use

within areas where the local ecology is a priority.

In conclusion, the change to white light provides

improved colour rendition for the visitor centre and a

high level of illumination for the car park. Careful

consideration should be made based on a number of

detailed location criteria before installing PIR sensors

and changing to white light, including financial and

environmental considerations.

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Abbreviations and definitions

BLISS Better Lighting in Sustainable Streets

BS British Standard

CCT Correlated Colour Temperature

CMS Central Management System

CO2 Carbon Dioxide

CPO Cosmopolis

CRI/ Ra Colour Rendering Index

DNO Distribution Network Operator

E Illuminance

E1,2,3,4 Environmental zone classification

Eave Average illuminance

Emin Minimum maintained illuminance

EAC Estimated Annual Consumption

EN European Standard

FCO Full cut-off

G Class Luminous intensity classification

HPS High Pressure Sodium

I Light Intensity

ILP Institution of Lighting Professionals

IMD Index of Multiple Deprivation

K Kelvin

kWh Kilowatt Hour

L Luminance

LED Light Emitting Diode

lm/W Lumens per watt

LPS Low Pressure Sodium

LSOA Lower Super Output Area

lx Lux

ONS Office for National Statistics

PNC Private Network Cable

S Class Subsidiary road class

TCS Technical Case Study

TCO Total Cost of Ownership

ULOR Upward Light Output Ratio

UMS Unmetered Supply

Uo Overall uniformity

UV Ultra Violet

W Watts

WEEE Waste Electrical and Electronic

Equipment

For additional information contact Lead Partner St.Helens Council;

+44 1744 676381 rorylingham@sthelens.gov.uk www.bliss-streetlab.eu