Jumper idea....

Summary
The idea is to encourage people to adapt their inside clothing to match the outside climate. This means wearing less clothes in the summer and more clothes in the winter, thus placing less load on the heating and cooling systems, resulting in decreased energy use and carbon emissions.
Initially, I feel that we should look at applying this to homeowners, because if we try to apply it to an office it would mean that all workers in an office would have to coordinate in order to wear similar clothing every day. If anybody is feeling particularly adventurous it may be possible to come up with a way of going about this. Aiming at homeowners means we only have to look at the heating system, as the vast majority of homes in the UK don't have any form of cooling.
Therefore, the idea is to give out second hand jumpers (in some way- covered shortly) for people to wear around the house so that they can turn the thermostat down a few degrees.
I believe this idea gives us a great basis to cary out some fairly in-depth engineering calculations that will set us apart as engineers at a festival of architecture.

Building services design
It may be a good idea to give a brief background of design in building services engineering. Design in the UK is usually based on guidance given in the CIBSE Guides (Chartered Institute of Building Services Engineers).
The first thing to do in any design is to find out what conditions need to be maintained in order to keep the occupants comfortable. Comfort encompasses many different factors, but for the purposes of this summary it can be said that a certain temperature range needs to be maintained. This varies with the type of building (dwelling, office, airport etc.) and also the season (winter or summer). The temperature range to be maintained depends on what the occupants are doing, defined by the Met, and what they are wearing, defined by the Clo. I believe that the comfort temperature in a dwelling in the winter is something like 22-24C, with fairly light clothing and doing little activity.
In the heating season (late autumn to early spring, usually about 30 weeks) the required temperature may be decreased by increasing the Met level or by increasing the Clo level. Realistically it would not be possible to increase the Met level, although I do remember something a few years back when all the workers in an office had their computers in front of a treadmill, which was a way of tackling obesity. But that was in America. Moving on....so the best way to decrease the temperature requirement is to encourage people to wear more clothes, which is where the idea of giving jumpers out comes in.

The calculation
There would be a number of ways to carry out the calculation. The following paragraphs detail how you would do this by following CIBSE guidance, however it must be remembered that, as a design guide, CIBSE is inherently conservative. Alternative methods may give results of larger carbon savings, but we could look into that.

• Determine the amount, in degrees C, that the building temperature can be decreased by (whilst keeping the occupants comfortable) by wearing a jumper. CIBSE Guide A has the following:
• Thin jumper: -0.7C
• Medium jumper: -1.4C
• Thick jumper: -2.1C
• Next, the amount of energy used by the heating system for each scenario (no jumper, thin jumper, medium jumper, thick jumper) can be calculated by doing a Degree Days calculation, which gives the average output of the boiler in kW over the heating season.
• The amount of energy saved for each type of jumper is calculated by subtracting the energy use from the energy use from wearing no jumper (if that makes sense! This is simple, just hard to explain in words!)
• The energy saving can then be converted to a carbon saving by multiplying by the Energy-CO2 conversion factor. For natural gas, which most boilers are, the conversion factor is 0.055 kgCO2/kWh.

Delivery

A few ideas of how this can be delivered in practicality........

• A drive for jumper donations from Ramboll employees. There are 10,000 of us!
• Partnership with local trade (don't forget, sustainability does not stop at materials and energy- it includes trade, business, happiness, health, friendship, love.......). Would work well in a cool place of London with boutiques and second hand shops.
• Display jumpers on 3 racks- S, M and L. However, these are not based on the actual size, but the thickness of the jumper. That is, S for a thin jumper with small carbon savings, M for a medium thickness jumper and L for a thick jumper with the largest carbon savings.
• A large jumper to display the amount of carbon that can be saved. Can be made from recycled material, and have some sort of practical use. Bear in mind that this thing would be pretty big- apparently the average carbon footprint for a person in the UK is 10 tonnes. Density of CO2 is about 1.9kg/m3, so 10 tonnes CO2 is equivalent to ~5,500m3. That is accounting for EVERYTHING, so would be smaller if you only account for CO2 emissions arising from activities in the house. It might be possible to source a fashion company who have some end-of-the-line jumpers they are looking to get rid of and use these to build the structure.
• We don't actually HAVE to give out jumpers, just put across the idea of wearing extra clothes indoors.
• Hopefully more to follow.....