Climate Change

Causes of climate fluctuation

To be able to see the current changes in climate in context, it will be necessary to consider the causes of dramatic changes in the past. A major cause of climate fluctuation has been the variation in the Earth's axial tilt and the path of its orbit round the sun. The Earth is subject to the influence of neighbouring planets. Their orbits produce a fluctuating gravitational pull on the Earth, affecting the angle of its axis. As the Earth wobbles, vast ice sheets wax and wane over a cycle called...

Mechanically assisted ventilation

Portcullis House Ventilation System

Rotating cowls was the system adopted by Michael Hopkins and Partners with Ove Arup and Partners in the Nottingham University Jubilee Campus Figure 12.9 . This ventilation system is the successor to Hopkins' and Arup's innovations at the Inland Revenue HQ also in Nottingham, and Portcullis House, Westminster. These led to a low pressure mechanical system linked to heat recovery via a thermal wheel which recovers 84 per cent of the exhaust heat. The mechanical system requires 51 000 kWh per year...

Unassisted natural ventilation

Lanchester Library Ventilation

Pioneers of natural ventilation are Alan Short and Brian Ford in association with Max Fordham. Their first groundbreaking building in the UK was the Queen's Engineering Building at Leicester de Montfort University Short Ford and Partners . This building has been well documented and a particularly useful reference is Thomas, R. ed. 1996 Environmental Design, E amp FN Spon. Maintaining the principle of pure natural ventilation without mechanical assistance is the Coventry University Library, the...

Demonstration House for the Future South Wales

Cross Section Pic Pellette Stove

A competition winning 'House for the Future' has been designed by Jestico Wiles within the grounds of the Musuem of Welsh Life in South Wales. Its two key attributes are sustainability and flexibility. It is capable of occupying a variety of situations a rural location, a greenfield suburban site or high density urban sites in terrace form. The structure of the house consists of a post and beam timber frame prefabricated from locally grown oak. A superinsulated timber stud wall faced with oak...

Towards the less unsustainable city

Woking Town Centre Chp

The ultimate challenge will be to transform existing towns and cities so that they become less of an 'ecological black hole'. The city is an epicentre of consumption, but also capable of being the highest visible manifestation of civilisation - 'civis' the city. Cities have powerful symbolic resonance which means that there are considerable constraints on change. Over the next 50 years, barring catastrophes like sea level rise, the basic form and infrastructure of European cities will not...

Glenwood Park Atlanta Georgia

Www Progetto

Due to be completed in 2006, Glenwood Park (Figure 20.3) aims to be 'a model of environmentally conscious urbanism' according to its developer Charles Brewer. The site is two miles east of downtown Atlanta and the developers have managed to 'civilise' a state highway, converting it to the development's main street with traffic calming Glenwood Park neighbourhood as proposed measures and lined with trees and shops. The object is to be pedestrian friendly 'to create a sociable, walkable community...

Emergent technologies and future prospects

No other century has begun with such an awareness of the potential for change and of the uncertainties that underlie that perception. The best we can do is identify the developing technologies and socio-economic trends that are clearly discernible and extrapolate from them. There are some predictions we can make with reasonable confidence and consider the implications for architects and related professions. There is little doubt that global warming will trigger changes that will fundamentally...

Ecological City of Tomorrow Malmo Sweden

Bo01 City Tomorrow Malmo

A European Commission demonstration project is almost completed in Malmo, comprising a whole new district consisting of housing, shops, offices and other services. It aims to be a zero net energy scheme, with its 11 GWh year energy demand making no net contribution to carbon dioxide CO2 emissions. It is being built on a reclaimed industrial site by the Ribersborg beach and close to the historic centre of Malmo. The project is the first phase of a 10 year programme to make the city of Malmo a...

Tidal energy

Working Principle Tidal Fences

Tidal energy is predictable to the minute for at least the rest of the century. Tide levels can be affected by storm surges as experienced dramatically in the UK in 1953. The British Isles benefit from some of the greatest tidal ranges in Europe. In summary, there are at least four technologies that can exploit the action of the tides, offering reliable electricity in the multi-gigawatt range. They are Trapping water at high tide and releasing it when there is an adequate head is an ancient...

High and superinsulation

Jaywick Green

In recent years attention has been focused towards the use of very thick layers of insulation within the building fabric in order to minimise heat flow. This technique has become known as superinsulation. The use of superinsulation has so far been best demonstrated at the domestic scale. This may be partly due to the problems of overheating experienced in many larger, deeper plan commercial buildings, problems which override the benefits of reduced winter heating requirements. In the future,...

Solar design Passive solar design

Wind Rose Template

Since the sun drives every aspect of the climate it is logical to describe the techniques adopted in buildings to take advantage of this fact as 'solar design'. The most basic response is referred to as 'passive solar design'. In this case buildings are designed to take full advantage of solar gain without any intermediate operations. Access to solar radiation is determined by a number of conditions the sun's position relative to the principal facades of the building solar altitude and azimuth...

The prospects for wood

Bre Garston

The House of the Future raises the question of the structural use of timber in buildings. Timber scores well on the sustainability scale, provided it is obtained from an accredited source such as the Forestry Stewardship Council. The Weald and Downland Open Air Museum 7 miles north of Chichester is a national centre for the conservation and study of traditional timber-framed buildings. The Conservation Centre explores new techniques in greenwood timber construction. Edward Cullinan Architects...

Beddington Zero Energy Development BedZED

Bedzed Diagrama

BedZED is not just another low energy housing scheme, it is a prescription for a social revolution a prototype of how we should live in the twenty-first century if we are to enjoy a sustainable future Figure 18.7 . The design was led by Bill Dunster Architects who are one of the UK's top evangelists for ecologically sustainable architecture with the services and energy strategy developed by Arup Associates. The Innovative Peabody Trust commissioned this development as an ultra-low energy mixed...

The National Assembly for Wales Richard Rogers Partnership

Suspended Ceiling Detailing Glass Facade

Following devolution, the Principality of Wales was granted greater autonomy resulting in the need for an assembly building for which the Richard Rogers Partnership was appointed architects with environmental engineer BDSP. It is a classic example of architect and engineer working in concert from the earliest stage of the project. The design brief was for a building which reflected the democratic nature of government whilst also being a landmark example of low energy design. It also has to last...

The David Wilson Millennium Eco House

Natural Ventilation During Winter

A demonstration Eco-House has been built in the grounds of the School of the Built Environment, University of Nottingham Figure 8.3 . It is designed as a research facility and a flexible platform for the range of systems appropriate to housing. Its features are PV tiles integrated into conventional slates providing 1250 kWh year solar collectors of the vacuum tube type on the south elevation to meet the demand for domestic hot water light pipe illuminating an internal bathroom and providing...

Chapter Predictions

Lowestoft Coastal Erosion

There is considerable scientific research effort being targeted on the likely consequences of climate change particularly within the scenario that the industrialised nations will continue indefinitely with 'business as usual' (BaU). This BaU scenario assumes some changes and improvements in efficiency in technology. Here are some of the predictions. Historic sea levels are well recorded in the Bahamas and Bermuda because these islands have not been subject to tectonic rise and fall. Ancient...

Energy for the future

If demand continues to rise at the present rate it is expected that most of the world's fossil fuel resources will run out around the middle of this century. There are still those who put their faith in the commercial application of nuclear fusion perhaps relying on the fact that an energy vacuum will radically alter the definition of 'commercial'. However, this goal still seems as elusive as ever. On a global scale there is no real optimism about the capacity of current renewable technology to...

Facilitates heat recovery

Solar Shading Light Shelf

An example of a climate facade building is the office development at 88 Wood Street in the City of London by the Richard Rogers Partnership RRP . The requirement was for floor to ceiling glazing which can create a problem of solar gain which is exacerbated by the heat from computers and, in this case, a high services loading. The facade developed by RRP and Ove Arup and Partners consists of a double glazed external skin made up of some of the world's largest double glazed units measuring 3 m X...

Types of smallscale wind turbine

Spiralf Rmige Wind Turbine Bilder

Most small systems have a direct drive permanent magnet generator which limits mechanical transmission losses. Systems under 2 kW usually have a 24-48 volt capacity aimed at battery charging or a DC circuit rather than having grid compatibility. Up to the present, horizontal axis machines are much more in evidence that the vertical axis type even at this scale. These machines have efficient braking systems for when wind speed is excessive. Some even tip backwards in high winds adopting the...

Building integrated systems

Altechnica Turbine

The Vivo building illustrates one version of a building integrated wind generating system. There is increasing interest in the way that the design of buildings can incorporate renewable technologies including wind turbines. Up to now such machines have been regarded as adjunct to buildings but a concept patented by Altechnica of Milton Keynes demonstrates how multiple turbines can become a feature of the design. The system is designed to be mounted on the ridge of a roof or at the apex of a...

Points raised in the report relevant to housing

Housing built to 2002 Building Regulations will be uncomfortably warm to live in by 2020. By 2080 internal temperatures could reach 40 C. It suggests that air conditioning and mechanical ventilation will be necessary, adding that the air conditioning should be driven by PVs or other renewable energy sources. Natural ventilation will be counterproductive when outside temperature exceeds internal temperature. It recommends masonry buildings with high thermal mass over timber frame lightweight...

Small wind turbines

Wind Catchers

In this context 'small' means wind machines that are scaled from a few watts to 20 kW. Machines between 1 and 5 kW may be used to provide either direct current DC or alternating current AC . They are mainly confined to the domestic level and are often used to charge batteries. The larger machines are suitable for commercial industrial buildings and groups of houses. Small-scale electricity production on site has economic disadvantages in the UK given the present buy-in rates for small...

The ecological tower

Foster Swiss Tower Plans

Surely an oxymoron The orthodox 'green' would rule out anything above about 12 storeys since this is the height at which natural ventilation in the western European climate zone is said to become impracticable. Tower blocks usually require a heavy engineering services system. Also the construction energy costs rise significantly every five floors or so. However, the ecological tower block has its advocates, most notably Ken Yeang from Kuala Lumpur. He pioneered the idea of gardens in the sky...

Low energy Conference Centre Earth Centre Doncaster

Earth Centre Conference Centre Doncaster

This is a building built to the highest super-insulation standards which is no less than we would expect from its architect, Bill Dunster. It has natural wind-driven ventilation with heat recovery from exhaust air transferred to incoming air. Solar collectors on the roof direct warm water to a calorifier in an underground insulated 400 m3 tank. Heat is stored over the summer to be circulated throughout the winter, with a wood burning stove for backup heat. A wind generator mounted in the boiler...

The evidence

There has been a marked increase in the incidence and severity of storms over recent decades. Over the past 50 years high pressure systems have increased by an average of three millibars whilst low pressure troughs have deepened by the same amount, thereby intensifying the dynamics of weather systems. Greater extremes of the hydrological cycle are leading, on the one hand, to increased area of desert, and, on the other, greater intensity of rain storms which increase run-off and erosion of...

Heat reflecting and heat absorbing glazing

These products are usually considered for application in situations where overheating poses a risk. Visible light and solar heat gain are both parts of the electromagnetic spectrum of energy emitted by the sun. The interaction of glazing with light and solar heat has three components reflection, absorption and transmission. Modifications in the proportions of reflected, absorbed and transmitted radiation could be engineered by changing the glazing system properties. There are several ways of...

Photovoltaic applications

Mont Cenis Academy Complex Germany

Commercial buildings have perhaps the greatest potential for PV cells to be integrated into their glazing as well as being roof mounted. Even at the present state of the technology, Ove Arup and Partners estimate that one third of the electricity needed to run an office complex could come from PVs with only a 2 per cent addition to the building cost. The main advantage of commercial application is that offices use most of their energy during daylight hours. The case study of the Zicer building...

Microcombined heat and power CHP

It is interesting how two nineteenth century technologies, the Stirling engine and the fuel cell, are only now coming into their own. Invented by Robert Stirling in 1816, the engine that bears his name is described as an 'external combustion engine'. This is because heat is applied to the outside of the unit to heat up a gas within a sealed cylinder. The heat source is at one end of the cylinder whilst the cooling takes place at the opposite end. The internal piston is driven by the successive...

Flywheel technology

The problem with flywheels is that the G-forces can cause a catastrophic explosion. Space technology is the driving force behind the development of superfast flywheels that can store a considerable quantity of kinetic energy to be converted into electricity. The future seems to point to materials like composites of carbon fibre and epoxy resin. However, early in the 1990s research in Japan was developing a 3 m flywheel made from stainless steel levitating between powerful magnetic fields...

Passive solar energy

Advocates of passive solar design have been around for many decades and the prize-winning schemes in a European competition for passive solar housing mounted in 1980 show that the technology has not advanced significantly since that time. However, the intensification of the global warming debate has led to increasing pressure to design buildings which make maximum use of free solar gains for heating, cooling and lighting. This will be considered in detail in later chapters. Because it displaces...

Active solar thermal systems

Seasonal Thermal Heat Storage

A distinction must be drawn between passive means of utilising the thermal heat of the sun, discussed earlier, and those of a more 'active' nature. Active systems take solar gain a step further than passive solar. They convert direct solar radiation into another form of energy. Solar collectors preheat water using a closed circuit calorifier. The emergence of Legionella has highlighted the need to store hot water at a temperature above 60oC which means that for most of the year in temperate...

Cavity filling

Council Flat Balcony

Where there are cavity walls injecting insulation through holes drilled at regular intervals is a common practice. However, caution should be exercised regarding the kind of insulation selected and the bona fides of the installation contractor. Post-completion inspections have discovered a number of cases of fraud where only a notional amount of insulation has been injected. Properly installed cavity filled insulation can have a significant impact on the thermal performance. In the Penwith...

Climate change

The carbon cycle and current imbalance. Evidence of past fluctuations and link between global temperature and CO2 in the atmosphere. Rise in sea level over the past 150 years rise in surface global temperature and temperature records in the last decade increasing intensity and frequency of storms and floods severe heat episodes migration to temperate zones of subtropical diseases melting of polar ice and glaciers. Present position compared with pre-industrial in...

Photochromic thermochromic and electrochromic glass

Each of these terms describes a variety of glazing in which the transmission properties are variable. Extensive opportunities exist for the development of some of these technologies to allow dynamic control of light and heat gain to match building and occupant requirements. Photochromic devices change transmission in response to prevailing radiation levels. Small examples have been in everyday use for some years in the form of sunglasses and spectacles. These react automatically to light...

Photovoltaics

The amount of energy supplied to the Earth by the sun is five orders of magnitude larger than the energy needed to sustain modern civilisation. One of the most promising systems for converting this solar radiation into usable energy is the photovoltaic (PV) cell. PV materials generate direct electrical current (DC) when exposed to light. The uniqueness of PV generation is that it is based on the 'photoelectric quantum effect in semi-conductors' which means it has no moving parts and requires...

The principle of photovoltaic cells PVs

Principle Photovoltaic Power

PVs are devices which convert light directly into electricity. At present most PVs consist of two thin layers of a semi-conducting material, each layer having different electrical characteristics. In most common PV cells both layers are made from silicon but with different, finely calculated amounts of impurities p-type and n-type. The introduction of impurities is known as 'doping'. As a result of the doping one layer of silicon is negatively charged (n-type) and has a surplus of electrons....

Next generation solar cells

Part Gratzel Cell

From the point of view of buildings, the most obvious renewable electricity source is the solar cell. High unit cost is the barrier which is preventing production achieving economies of scale. But here again things could be about to change. The solar cells of the future are likely to use thin film technology, for example titanium-oxide coated nanocrystals with ruthenium dye which mimic photosynthesis and which are now being developed in Switzerland. They absorb light strongly in the red and...

What is being done

The core of the problem lies in the disparity between the industrial and developing countries in terms of carbon dioxide emission per head. Despite all the international conventions carbon dioxide emissions from developed countries are showing little sign of abating. The USA at twice the European average is still increasing its emissions which currently stand at 23 per cent of the world's total. The average citizen in the North American continent is responsible for around 6 tonnes of carbon per...

Three technologies the marine environment

Two quotes set the scene for this chapter A sustainable energy system is probably the single most important milestone in our efforts to create a sustainable future . . . Decarbonisation of the energy system is task number one. Oystein Dahle, Chairman. Worldwatch Institute Global civilisation can only escape the life-threatening fossil-fuel resource trap if every effort is made to bring about an immediate transition to renewable and environmentally sustainable resources and thereby end the...

Tools for environmental design

The three main categories of passive solar design, along with their subdivisions, are most usually applied within domestic-scale designs. However, similar principles have been analysed with reference to commercial developments. One assessment method that addresses this sector is the Lighting and Thermal Value of Glazing Method - the 'LT Method', developed in the UK. This method reduces a building to an orthogonal plan with core and perimeter zones. The perimeter zone is that which is subject to...

Chapter Lighting and human Fifteen failings

Artificial lighting is a major factor in deciding the quality of the internal environment of offices. It is also a serious contributor to carbon dioxide, (CO2) emissions accounting in the US, for example, for up to 30 per cent of total electricity use (ScientificAmerican, March 2001). For these reasons it is a subject that warrants special attention. Design studies suggest that considerable energy savings can be made by maximising natural light, particularly if it is linked to automatic...

Hydroelectric generation

Hydroelectric schemes which exploit height difference in the flow path of water are the oldest method of generation from water. It involves damming a watercourse to create the necessary pressure to drive high speed impulse turbines. The Boulder Dam scheme in the USA was the first large-scale project implemented in the 1930s as a means of driving the country out of recession. One of the first major projects to be completed after the Second World War was the Aswan Dam scheme initiated by Colonel...