Embodied Energy Saved In The Rehabilitation of Old Industrial Buildings
in Scotland (Scoţia) Salvează energia! – Reciclarea flexibilă a
patrimoniului industrial
Mark WatsonHistoric [email protected]
Open hearth steel, Nizhny Tagil, Russia, 1994/ Anina, Banat, Romania
Flooding of a converted textile mill.
Climate change affects heritage
• Ironbridge World Heritage Site, UK
• A door records floods from 1929 to 2008• We need to monitor
impacts of climate change over time
Adapt and mitigate, Kyoto to Copenhagen
• How to capture carbon?• reduce emissions? or • ensure that the carbon
already spent is used again and again?
At Port Dundas Distillery in Glasgow
The challenge of climate change,
The carbon footprint is
• a measure of the exclusive total amount of carbon dioxide emissions that is directly and indirectly caused by an activity or is accumulated over the life stages of a product
• a city has one too!
Whole life costing
1. Whole life costing shows that re-use of buildings can reduce the carbon emissions arising from demolition and building anew, and go some way towards reversing the harm industry has brought to the environment through climate change.
2. The more is kept, the better the outcome in terms of waste not taken to landfill.
3. Existing materials contain embodied energy already spent, and less energy need be devoted to bringing in new building materials
Historic buildings capture embodied energy
• Historic buildings can make a significant contribution towards meeting targets for climate change reduction. They are
• already built, can be • adapted to meet new purposes and • upgraded in ways sympathetic to their character
and performance.
Ettrick Mill, Selkirk, before and after
Solar thermal panels in Edinburgh WHS, but no use of hydro power in Grandholm Mills, Aberdeen
EPC excellent for Ettrick Mill, Eildon Housing Association, 2009
External insulation to traditional wooden houses in Pispala, Finland
Cooling
• And in southern Europe, Australia and USA everyone must have air conditioning, with its own
• carbon energy cost and • need to seal up buildings
Emissions in use or Embodied energy?
• Operational savings (by insulation or renewable energy) take many years to match these and rely on human action to keep up proper maintenance. Benefits could be lost if refurbishment cycles shorten.
• Savings in embodied energy achieve immediate reductions in carbon and are passive, don’t need ongoing attention.
Ventilation extracts from the Lighthouse/ Herald building in Glasgow by CR MacKintosh
• Plenum heating:• Cool fresh air drawn in at
the bottom, warms up and rises as it becomes stale, to be naturally dispersed through these ventilators.
yet
• there are environmentalists who say that the real problem lies in all the old buildings that are “hard to treat”. If only their demolition could be speeded up the earth would be more sustainable.
Finding: The current demolition rate needs to be increased fourfold, targeted at the most inefficient and unhealthy homes.
http://www.eci.ox.ac.uk/research/energy/40house.php • But would it?
40% House campaign demands more demolition
Under the 40% House scenario, the demolition rate increases from 20,000 per year now to 80,000 p.a. in 2016 and stays at this level until 2050, giving a total demolition over the whole period 2005-2050 of 3.2 million properties.
Savings beyond those would come from increasing the demolition rate further to 150,000 per year and would reduce the notional lifespan of the average building to 250 years.
To get down to 120 years, demolition would have to rise to 234,000 per year. This would enable energy consumption for space and water heating to reduce by 24%
234,000 dwellings demolished in the UK in a single year means
= 9% of all Scottish dwellings, or more than:
= the total number in Edinburgh (217,654)
• A lot of celebrities have signed up to support the campaign.
Pulteneytown Townscape Heritage Initiative, Wick 2001/2005
• Thomas Telford layout of a fishing town with cooperages, smokehouses etc• So this should have been demolished, not refurbished, to help achieve
emissions targets
The solution?
• A ‘passiv haus’ imported from Germany to Scotland 2008
• Good thermal efficiency
• but it’s still for sale • few others are now
being built
Scottish Government National Performance Framework
• National Indicator: Increase the rate of new House Building
• Outcome: an increase in terms of households in conservation areas (despite falls elsewhere):
• % of households in conservation areas • in 2008: 9.2% • in 2010: 9.6% (262,036)So growth of smaller households in urban centres is
helped, not impeded, by conservation
Biggest property deal in Scotland, January-May 2009 Kilmarnock THI: Johnnie Walker’s warehouse to East Ayrshire council offices
Building conservation meets the recycling protocol by
1. reducing need to build new by re-use of buildings;
2. re-using buildings and their components, reclaiming where practicable materials such as roofing slate, brick and building stone
3. recycling and remanufacturing of materials: easier say where lime is the binder rather than cement
(in descending order of preference):
Refit cycles
• Short design life and refit cycles increase lifetime emissions. Embodied assessment captures this. SAP assessment of emissions in use does not.
• right: Logie Schoolhouse, a Europa Nostra award winner, in its 3rd use (school/ church/ house) in 180 years
• = 60-year cycle
Traditional thermal mass (Logie Schoolhouse built of clay)
• Built and maintained from locally sourced materials, buildings have traditionally relied on their thermal mass for warmth and cooling, for natural light and ventilation. Knowledge of these systems help designers of modern green buildings.
Healthy buildings: don’t seal them up
Buildings traditionally rely on:• Thermal mass for an even
climate• Natural light and ventilation• Vapour-permeable walls to
absorb and release moistureFor insulation options see http://
www.changeworks.org.uk/content.php?linkid=373
Long life/ Loose fit buildings
• The most adaptable buildings may be an old industrial building that has gone through several changes of use already, e.g.
• Sugar refinery/ VAT69 whisky bond, and now offices in an Edinburgh mixed-use development
Bonnington Bond, Leith, Edinburgh
Whisky warehouse ->c.1908Sugar refinery / store -> 1865 McEwan’s Maltings -> 1865
Scheme A is contrary to use zoning: Scheme B fits zoning
With the May T Watts carbon calculator , if Bond were demolished
• Embodied energy invested (heavy construction) 116,400,000 MBTU
• demolition if totally removed +1,440,000,000 BTU
• new build as light construction for industrial units +64,990,000 MBTU
• = 182,830,000 MBTU total would be used
British Thermal Unit
• 1 BTU= one match• 1 MBTU= 1,000 cu.ft. of gas or approx I joule • 1 Million BTU = 1 055.06 megajoulesOther measures of embodied energy in materials
are found in MJ so for example,• uPVC window 620 MJ/m = 2980 MJ• Timber window 207 MJ/m = 995 MJ
Bonnington Bond’s conversion has saved:
182,830,000 MBTU =• 1,589,826 litres of
gasoline or• 192 896 619 800 000
joules or• 192,897 timber windows
or• 65,000 UPVC windows
The Greenest Building is the One Already Built
• EMBODIED ENERGY CALCULATOR• To use this calculator, begin by choosing your property
type from the box on the left. In the box labelled gross floor area enter your building's total square footage. Click calculate to get the amount of energy "embodied" (that's the total energy spent in the production of a building, from the manufacture of materials to their delivery to construction) in your building!
X sq. ft. = MBTU Embodied Energy Investment*
95000 BTU/lb Primary Non-Ferrous Products 25000 BTU/lb Primary Iron & Steel Products 400000 BTU/cf Stone & Clay Products: Brick 96000 BTU/cf Stone & Clay Products: Concrete 40000 BTU/sq. ft. Glass Products: Plate 15000 BTU/sq. ft. Glass Products: Windows 2000 BTU/sq. ft. Asphalt Products 1000 BTU/sq. ft. Paints 450 ft2 per gallon9000 BTU/BDFT Wood Products
Embodied energyMaterial
Life Cycle Assessment or Whole-life costing
• LCA can consider a range of environmental impacts such as
• resource depletion,
• energy and water use,
• greenhouse emissions,
• waste generation and so on.
http://www.thegreenestbuilding.org/survey.html
LCA
• As the energy efficiency of houses and appliances increases, embodied energy will become increasingly important. Reuse of building materials commonly saves about 95% of embodied energy that would otherwise be wasted. http://greenestbuildingistheonealreadybuilt.blogspot.com/
General Post Office or Waverleygate Edinburgh
New home for Creative Scotland
Case study Edinburgh General Post Office or Waverleygate
• Façade retention was a hugely expensive and time consuming process
• countless lorries took rubble, concrete and steel away over many months.
Work underway: the building is cored/gutted
• Then new floors were brought in around a new lightwell.
• The notional value of the building justifies the investment made in it by institutional investors such as pension funds.
Emissions saved in use?
• Waverleygate claims to be a very green office in terms of its energy performance:
• chilled beams for cooling (£6.70 per m2, 25% cheaper than other systems)
• A green roof.
Waverleygate embodied energy cost
• Calculating performance in use is not easy while empty. Saved emissions could only count if those emissions had previously been made elsewhere in a leaky office.
• The environmental costs of transporting so much structure away, and bringing so much new structure in - the embodied energy cost- outweigh any benefit until it is occupied.
Using thegreenestbuilding calculator, to demolish the GPO means:
Embodied energy lost +Demolition energy+New embodied energy =Energy lost and spent:
http://www.thegreenestbuilding.org.
• 211,313,530 MBTU• 2,614,188,000 BTU• 211,313,530 MBTU• 422,627,277 MBTU• =3,675,020 gallons of
petrol/gasoline
What does 3,675,020 gallons of petrol/gasoline mean?
• It would take you 283,298,421 Km in a Skoda Fabia
from Earth to Mars or• 79,981,635 Km in a
Ferrari from Mercury to the Sun
Edinburgh General Post Office, steel and concrete
What if some of the interior had been preserved?
• No allowance is made by WRAP in UK
• But in USA it would get some credit through LEED
US Green Building Council
America is more green!
• The US approach gives some credit for use or re-use of a building. See http://www.usgbc.org/Default.aspx
• Keeping more of other walls and floor structure means a much greater saving in terms of the overall carbon footprint. Example of a Scottish wool mill: Tower Mill in Hawick
Tower Mill, Hawick, built 1851 over River Slitrig
Tower Mill, Drumlanrig Tower, Heritage Hub
Tower Mill floorspace
• 21,635.44sq ft before the work
• 20,343.77sq ft. after• (In fact the building is
bigger but some floors have been removed in the cinema)
Carbon calculator if Tower Mill were demolished instead
• extant embodied energy• if demolished• new work total LOST
• 29,856,300 MBTU• 201,209,592 BTU• 58,119,900 MBTU
What if Tower Mill were demolished instead?
• total 58,119,900 MBTU LOST AND SPENT
• = 505,390 GALLONS• = 258,015 LBS OFCO2• = 3.5 US households in a
year• = 61 320 087 MJ• = 22,000 UPVC windows
summary
• As emissions in use fall, embodied carbon will become the main area for achieving sustainable development.
• Cultural heritage conservation people need to learn the language of energy conservation
• We cannot just assume that energy conservation will take the same side as building conservation, but
• Industrial buildings, due to the often high embodied energy in their heavy construction, will play an important part.
Multumesc!