Zero Emission Project

The conclusion of the previous article was clear: if we could reduce to zero the total CO2 emissions of every household in Britain, we would wipe out 131 millions of tCO2 per year.

The British government has set out an ambitious target: to reduce the total amount of British emissions by 60% by 2050. According to the British House of Commons, in 2004 residential emissions contributed around 30% to UK total carbon emission. The emissions from the existing 25 million dwellings in the UK in 2004 were estimated at 40 Mtonnes of carbon (MtC) a year.

My estimate regarding 26.2 millions dwellings in 2011 is about three times as much as the House of Commons’ estimate. It is fair to say that I worked out the estimate considering just very old semidetached houses, while the housing stock in Britain is formed by a number of newer houses and small apartments in blocks of flats as well. However, I wouldn’t be as optimistic as the House of Commons and I would say that probably we could set the figure half way in between the two, say 80 millions of tCO2.

Figure 4 - Typical British Victorian terraced houses

In any case it is well clear that this huge amount of carbon dioxide doesn't disappear just joining thousands of good-will campaigns (which are all important anyway) and without a great commitment, an extraordinary leadership and a number of unpopular choices.

We need to have this picture very clear in mind: this target is not going to be achieved if we want to make everyone happy. Either we are serious about it and we fight our way through, making unpopular decisions, or we give up now.

How much could we reduce our household CO2 emissions, exploiting the available technologies?

Let's consider different scenarios and analyse the energy consumption of some typical dwellings that we can find across Britain.

Energy consumption depends on many factors, such as the size, quality and age of the buildings, the insulation technologies adopted (if any), the energy efficiency of boilers, light bulbs, kitchen appliances and electronic gadgets, the outdoor climate, and, not insignificantly, the behaviour of the occupiers.

For these reasons, it is not easy to identify the typical average household in Britain, since its energy consumption is affected by many different factors.

What we can do is to take some possible examples and try to extrapolate an average British household consumption.

One of the worst scenarios in Britain is an old 100 m² three-bedroom Victorian detached house, with no insulation, single glazed windows, a 10 year-old inefficient gas boiler, old kitchen appliances, incandescent light bulbs, and occupiers that don't use their thermostat and don't care at all about their energy consumption. A household like this can easily consume 30000 KWh/year just for the heating, as documented by David MacKay, professor at the University of Cambridge, in his book Sustainable Energy.

30000 KWh of burned gas energy corresponds to about 5507 KgC02/year, using the conversion factor proposed by the National Energy Foundation.

A more responsible household, still living in an old 100 m² Victorian detached house, but maybe with double glazed windows and good use of their thermostat, could consume 20000 KWh/year for the heating, which is equivalent to 3672 KgC02/year.

An other example is a Victorian conversion. I currently live in a rented old two-bedroom 120 m² flat, which is part of a big Victorian house with high ceilings, double glazed windows and an old gas boiler. I strictly control the use of the central heating by carefully using the thermostat and the whole family tries to use hot water responsibly. The total annual average gas consumption is about 25000 KWh, which is about 4590 KgCO2, which is roughly the weight of an African elephant!

Figure 1 - An African elephant, 4.5t

Sadly, these examples represent the majority of the residential buildings in Britain. As reported by the Passive House Institute, the British housing stock is probably the worse across Europe.

It's time to give a more defined shape to Zero Emission Workspace and Zero Emission Xspace. So far the analysis has been pretty much focused on the technical aspects of the projects, such as the estimate of the electricity consumption of the proposed buildings and some possible solutions to realize them. We have gone through calculations about the energy generated by different kinds of micro-generation systems, the main concepts of Passive House design and a rough investment cost estimate.

What we still need to define in details is how a zero carbon building like the one previously described can contribute to a urban regeneration plan such as the Tolworth project. In particular, we need to clearly describe how the main stakeholders, i.e.:

• local communities
• local businesses
• local authorities

can benefit from the output of this project.

Although the targets will be primarily set for the local interests of Tolworth, the project should possibly bring social and economic benefits to a wider area, such as the Royal Borough of Kingston, South West London or even the whole South East England. The actual scope of the project and its subsequent outcome will depend on the number of partners that will take part in the project and the implementation details which will be set during the consultation and planning phase with all the stakeholders.

Since there is no doubt that the local community, local businesses and local authorities will be among the main beneficiaries of the project deliverables, we now have to clearly define what these benefits will possibly be.

Even though I am going to consider Tolworth as the area of development, all the points that follow can be applied to any area with similar characteristics and community and business regeneration needs.

The analysis is regarding all the services, events and business opportunities that can be provided by Zero Emission Xspace, which is one of the zero carbon projects proposed for the Tolworth Regeneration Strategy.

Figure 1 - How the local community will benefit from Zero Emission Xspace

The diagram in figure 1 shows some of the possible benefits to the local residents.

Here we are. One project, one town, one local community. Now I am going to explain what this idea is really about.

The main points I still need to clarify are where, why and how. I believe that the projects I have previously described (i.e. Zero Emission Workspace and Zero Emission Xspace) fit very well into the wider picture of the Tolworth project.

Tolworth is a small town centre within the borough of Kingston-upon-Thames and is part of the Greater London area. The Royal Borough of Kingston council set out a project in 2008 to help regenerate the Tolworth area and promote social and economic development and environmental improvement.

Figure 1 - Tolworth within Greater London

A number of specialist studies carried out on behalf of the council describe Tolworth as an area affected by many problems, such as traffic congestion, air pollution, lack of parking space, lack of a good mix of shops, sport and community facilities, a high number of vacant premises and a generally poor office-based business activity. Nonetheless Tolworth District Centre and the A240 corridor from Tolworth Broadway (to the north of the A3) to Tolworth rail station (to the south of the A3) have been identified as urban areas with great development potential.

Zero Emission Workspace has been designed to be a zero-carbon PassivHaus three storey commercial building, classified at Level 6 according to the Energy Saving Trust "Code for Sustainable Homes". Can it be redesigned to be something else?

The analysis carried out can actually be adapted to different kinds of buildings. The solution presented so far is just an example: there is nothing that stops us changing it from a commercial building to an exhibition centre, a gym or even a small high-tech residential housing development. Or we could think of something else. While a Passive House commercial building is great for businesses willing to make a concrete move towards a sustainable way of working, I would rather introduce this new building concept starting from the people. In fact, it would be excellent if potentially everyone benefited from such advanced technology.

Some possible options could be a school, a community library or a youth art centre. This way, everyone living in the area could appreciate the advantages of having a sustainable zero carbon building in their neighbourhood.

We'll go through such advantages later on; now, let's try to redo the maths for a community or educational building in general, bearing in mind that these kinds of buildings have many features in common, so it's not necessary to be too specific.

I'll keep considering a 3 storey building in order to have enough space for different kinds of activities.

As shown in figure 1, at ground floor we have an open space with a reception room and a large versatile communal area, which can be used for a number of different purposes, such as an exhibition area, a conference room or social space; a second room can be used as an audio/video media room, a reading room or a classroom.

At the first floor, a large room can host a theatre, a reading room or a big classroom and a second room can be used for visual art lessons and practice.

The third floor could feature a cafeteria, a computer lab and a painting room.

Figure 1 - Zero Emission Xspace - ground floor (click on the image to enlarge)

This project includes many innovative features which will indeed require some initial investments. Some of the technologies are available on the market off the shelf, but some others will be probably introduced as pilot projects.

Let’s go through a rough estimate of the initial investment costs. Table 1 shows a list of potential investments that are required by the project described in previous sections.

Table 1 – Zero Emission Workspace investment costs

Land – The estimate of the investment needed for the purchase of a suitable land bears a high level of uncertainty. The area required for the building is 600 m², thus, taking into account the space for the car park and the energy generation facilities, it is likely that an area of 10000 m² (2.5 acres) will be necessary, as illustrated in figure 2. Land cost varies between different locations across England, which means that it is possible to better estimate this figure only once the region has been identified.

As a gross estimate, we set the cost to £100K, which is a reasonable amount for an average land of this size. It is clear that this cost could be either half or twice as expensive as £100K, nonetheless this estimate gives at least the magnitude of the investment required.

Figure 1 – Zero Emission Workspace map