This document summarizes a workshop on low carbon buildings in the South West of England. It discusses how buildings account for a large portion of global energy usage and emissions, which is projected to increase significantly by 2050. The building sector provides great potential for cost-effective emissions reductions. It then provides examples of typical energy usage benchmarks for different building types and examines where the biggest opportunities for energy savings in buildings lie, such as lighting upgrades, HVAC improvements, and optimizing controls. Specific lighting and HVAC upgrade options are presented, typically resulting in energy reductions of 30-60% and 25-50% respectively.

1. Low Carbon South West Breakfast Workshop
Light & Energy
Tilly Shaw
tilly.shaw@energy-ts.com
21 November 2017

2. 1 - Light and Energy in Buildings
§ In 2010 buildings accounted
for 32% of total global final
energy use.
§ This may double or triple by
2050, due to global
demographic trends
§ The building sector has been
shown to provide the
greatest potential for
delivering significant cuts in
emissions at no cost
Sources: 1-IPCC AR5-Working Group 3 – Ch9; 2-UNEP Sustainable buildings and climate initiative.
Photo courtesy of aturkus / www.flickr.com under creative commons license.

3. 2 - Where is my energy going?
I think we’re fairly
energy-efficient,
but how can I be
sure?
ü Record your energy use, in kWh/year and £/year
ü Find the floor area for each type of space (for example server
room, office space)
ü Establish true operating hours and other potential “energy
drivers” for your building
ü Compare kWh/m2 to standard benchmarks, previous years, or
similar buildings
...set up your energy baseline
& compare to benchmarks

4. 3 – What does “good” look like?
0
100
200
300
400
500
600
Air
conditioned
office
Naturally
ventilated
office
Bank / Agency Small retail
outlet -
clothing
Small retail
outlet - food
Kilowatt-hours per m2floor area, per year
Electricity
Gas

5. 4 – Where are the big wins?
Air conditioned office - Electricity Use Catering
Heating and Cooling
Lighting
Office Equipment
ICT and Other
Naturally ventilated office - Electricity Use
Catering
Heating and Cooling
Lighting
Office Equipment
ICT and Other
Bank / Agency - Electricity Use
Heating and Cooling
Lighting
Office Equipment
ICT and Other
Source: CIBSE. Split by kilowatt-hours electric – (assumes space heating with gas)

6. 3 - Lighting: what could you save?
4 x 2ft T8 fluorescent panel 72W
• Cost to upgrade to 36W LED ~ £50 each
• Saving (office hours) ~ 75 kWh or £10 / yr
2 x 4ft T5 fluorescent tubes 56W
• Cost to upgrade to 32W LED ~ £40 (re-lamp)
• Savings (office hours) ~ 50 kWh or £5 / yr
Halogen GU10 50W
• Cost to upgrade to 7W LED ~ £10 each
• Savings (office hours) ~ 90 kWh or £12 / yr
Reviews have found that lighting retrofits in commercial buildings typically
reduce lighting energy use by 30 – 60% (+ maintenance savings)

7. 4 - HVAC: what could you save?
A review of commercial building retrofits found typical savings of 25-50%
HVAC consumption, through upgrading equipment and controls (without
changing the building envelope).
Heating ventilation and cooling can be complex but there are some simple
things everyone can ask about:
1. Is the plantroom equipment in “manual” or “in hand” mode?
2. Does heating and cooling occur at the same time in the same space?
3. Is the whole system adjusted to cope with a small problem area e.g.
cold spots near a large window or doorway?
If your answer to any of the above is “yes” then a review of controls
and/or zoning is likely to be cost-effective.

8. THANK YOU
Tilly Shaw
Technical Energy Centre Operations Manager
Energy & Technical Services
tilly.shaw@energy-ts.com
Tel: 01934 854 219
Mob: 07722 148 003