Climate Change: The Hard Choices Facing us

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Norwich Engineering Society 5th November 2007
Climate Change The Hard Choices Facing us What
the Engineer can do to help
Recipient of James Watt Medal 5th October 2007
Keith Tovey (???) MA, PhD, CEng, MICE,
CEnv Energy Science Director HSBC Director of
Low Carbon Innovation
CRed
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ZICER Building
Low Energy Building of the Year Award 2005
awarded by the Carbon Trust.

• Heating Energy consumption as new in 2003
  was reduced by further 57 by careful record
  keeping, management techniques and an adaptive
  approach to control.
• Incorporates 34 kW of Solar Panels on top floor

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Changes in Temperature
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Climate ChangeArctic meltdown 1979 - 2003

• Summer ice coverage of Arctic Polar Region
• Nasa satellite imagery

• 20 reduction in 24 years

Source Nasa http//www.nasa.gov/centers/goddard/n
ews/topstory/2003/1023esuice.html
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Options for Electricity Generation in 2020 -
Non-Renewable Methods
Nuclear New Build assumes one new station is
completed each year after 2018.
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Options for Electricity Generation in 2020 -
Renewable
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Options for Electricity Generation in 2020 -
Renewable
Area required to supply 5 of UK electricity
needs 300 sq km But energy needed to make PV
takes up to 8 years to pay back in UK.
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Options for Electricity Generation in 2020 -
Renewable

• Transport Fuels
• Biodiesel?
• Bioethanol?
• Compressed gas from
• methane from waste.

But Land Area required is very large - the area
of Norfolk and Suffolk would be needed to
generated just over 5 of UK electricity needs.
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Options for Electricity Generation in 2020 -
Renewable
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Options for Electricity Generation in 2020 -
Renewable
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Options for Electricity Generation in 2020 -
Renewable
Output 78 000 GWh per annum Sufficient for 13500
house in Orkney Save 40000 tonnes of CO2
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Options for Electricity Generation in 2020 -
Renewable
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Solar Energy - The BroadSol Project
Solar Collectors installed 27th January 2004
Annual Solar Gain 910 kWh
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Performance of a Solar Thermal System
Data collect 9th December 2006 30th October 2007
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It is all very well for South East, but what
about the North?
House on Westray, Orkney exploiting passive solar
energy from end of February
House in Lerwick, Shetland Isles with Solar
Panels - less than 15,000 people live north of
this in UK!
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Our Choices They are difficult Energy Security
There is a looming capacity shortfall Even with a
full deployment of renewables. A 10 reduction in
demand per house will see a rise of 7 in total
demand - Increased population decreased
household size

• Opted Out Coal Stations can only run for 20 000
  hours more and must close by 2015
• New Nuclear assumes completing 1 new nuclear
  station each year beyond 2018
• New Coal assumes completing 1 new coal station
  each year beyond 2018

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Our Choices They are difficult

• Do we want to exploit available renewables i.e
  onshore/offshore wind and biomass.
  Photovoltaics, tidal, wave are not options for
  next 20 years.
• If our answer is NO
• Do we want to see a renewal of nuclear power
• Are we happy with this and the
  other attendant risks?

• If our answer is NO
• Do we want to return to using coal?
• then carbon dioxide emissions will rise
  significantly
• unless we can develop carbon sequestration and
  apply it to ALL our
• COAL fired power stations within 10
  years - unlikely.

If our answer to coal is NO Do we want to leave
things are they are and see continued
exploitation of gas for both heating and
electricity generation? gtgtgtgtgtgt
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Our Choices They are difficult

• If our answer is YES
• By 2020
• we will be dependent on around 70 of our
  heating and electricity from GAS
• imported from countries like Russia, Iran,
  Iraq, Libya, Algeria
• Are we happy with this prospect? gtgtgtgtgtgt

If not We need even more substantial cuts in
energy use. Or are we prepared to sacrifice our
future to effects of Global Warming by using
coal? - the North Norfolk Coal Field? Aylsham
Colliery, North Walsham Pit?
Do we wish to reconsider our stance on
renewables? Inaction or delays in decision making
will lead us down the GAS option route and all
the attendant Security issues that raises.
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On average each person in UK causes the emission
of 9 tonnes of CO2 each year.
How many people know what 9 tonnes of CO2 looks
like?
5 hot air balloons per person per year. Around 4
million over Norfolk. In the developing world,
the average is under 1 balloon per person Is this
Fair?
"Nobody made a greater mistake than he who did
nothing because he thought he could do only a
little." Edmund Burke (1727 1797)
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Raising Awareness

• A tumble dryer uses 4 times as much energy as a
  washing machine. Using it 5 times a week will
  cost over 100 a year just for this appliance
  alone and emit over half a tonne of CO2.

• 10 gms of carbon dioxide has an equivalent volume
  of 1 party balloon.

• A Mobile Phone charger up to 20 kWh per year
• 1000 balloons each year. 10 kg CO2

• Standby on electrical appliances
• 60 kWh a year - 4000 balloons.

• Filling up with petrol (38 for a full tank
  40 litres)
• --------- 90 kg of CO2 (5 of
  one hot air balloon)

How far does one have to drive in a small family
car (e.g. 1400 cc Toyota Corolla) to emit as much
carbon dioxide as heating an old persons room for
1 hour?
1.6 miles
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Involve the local Community

• The residents on the island of Burray (Orkney)
  campaigned for a wind turbine.
• On average they are more than self-sufficient in
  electricity needs and indeed are a net exporter
  of electricity.
• Many of the Islanders bought shares in the
  project and are now reaping the reward.
• Orkney is hoping to be a zero net emitter of
  carbon dioxide by 2015.
• Even better things are happening on the Island of
  Westray.

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Involve the local Community
Even better things are happening on the Island of
Westray.
The Parish Kirk, and Community Centre are heated
by heat Pumps partly powered by Wind Turbines
Waste cooking oil from other islands is processed
into biodiesel for farm and other
vehicles. Ethanol used in process is obtained
from fermentation of harvested sea weed
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The ZICER Building - Description

• Four storeys high and a basement
• Total floor area of 2860 sq.m
• Two construction types

• Main part of the building
• High in thermal mass
• Air tight
• High insulation standards
• Triple glazing with low emissivity

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Operation of the Main Building

• Mechanically ventilated that utilizes hollow
  core ceiling slabs as supply air ducts to the
  space

Recovers 87 of Ventilation Heat Requirement.
Return stale air is extracted from each floor
Air enters the internal occupied space
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Importance of the Hollow Core Ceiling Slabs
The concrete hollow core ceiling slabs are used
to store heat and coolness at different times of
the year to provide comfortable and stable
temperatures
Winter Day
Winter day
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Importance of the Hollow Core Ceiling Slabs
The concrete hollow core ceiling slabs are used
to store heat and coolness at different times of
the year to provide comfortable and stable
temperatures
Winter Night
Winter night
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Importance of the Hollow Core Ceiling Slabs
The concrete hollow core ceiling slabs are used
to store heat and coolness at different times of
the year to provide comfortable and stable
temperatures
Summer Night night ventilation/free cooling
Draws out the heat accumulated during the day
Summer night
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Importance of the Hollow Core Ceiling Slabs
The concrete hollow core ceiling slabs are used
to store heat and coolness at different times of
the year to provide comfortable and stable
temperatures
Summer Day
Pre-cools the air before entering the occupied
space
Summer day
The concrete absorbs and stores the heat like a
radiator in reverse
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Thermal Properties of Buildings

• Heating energy requirement is strongly dependant
  on External Temperature.
• Thermal Lag in Heavy Weight Buildings means
  consumption requirements lags external
  temperature.
• Correlation with temperature suggests a thermal
  lag of 8 hours.
• Potential for predictive controls based on
  weather forecasts

Data collected 10th December 2006 April 29th
2007
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Good Management has reduced Energy Requirements
The space heating consumption has reduced by 57
But this has only been possible because of
realtively heavy weight construction
Acknowledgement Charlotte Turner
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Life Cycle Energy Requirements of ZICER as built
compared to other heating/cooling strategies
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54
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51
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61
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Comparison of Life Cycle Energy Requirements of
ZICER
Comparisons assume identical size, shape and
orientation
Compared to the Air-conditioned office, ZICER
recovers extra energy required in construction in
under 1 year.
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ZICER Building
Photo shows only part of top Floor

• Top floor is an exhibition area also to promote
  PV
• Windows are semi transparent
• Mono-crystalline PV on roof 27 kW in 10
  arrays
• Poly- crystalline on façade 6/7 kW in 3 arrays

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Arrangement of Cells on Facade
Individual cells are connected horizontally
If individual cells are connected vertically,
only those cells actually in shadow are affected.
As shadow covers one column all cells are inactive
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Use of PV generated energy
Peak output is 34 kW
Sometimes electricity is exported
Inverters are only 91 efficient
Most use is for computers
DC power packs are inefficient typically less
than 60 efficient
Need an integrated approach
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Conversion efficiency improvements Building
Scale CHP
Localised generation makes use of waste
heat. Reduces conversion losses significantly
61 Flue Losses
36 efficient
86 efficient
Engine heat Exchanger
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Conversion efficiency improvements
Before installation
After installation
This represents a 33 saving in carbon dioxide
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Conversion efficiency improvements
Load Factor of CHP Plant at UEA
Demand for Heat is low in summer plant cannot
be used effectively
More electricity could be generated in summer
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Conversion efficiency improvements
Normal Chilling
Adsorption Chilling
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A 1 MW Adsorption chiller

• Adsorption Heat pump uses Waste Heat from CHP
• Will provide most of chilling requirements in
  summer
• Will reduce electricity demand in summer
• Will increase electricity generated locally
• Save 500 700 tonnes Carbon Dioxide annually

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Results of the Big Switch-Off
With a concerted effort savings of 25 or more
are possible
How can these be translated into long term
savings?
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The Behavioural Dimension

• Household size has little impact on electricity
  consumption.
• Consumption varies by up to a factor of 9 for any
  given household size.
• Allowing for Income still shows a range of 6 or
  more.
• Education/Awareness is important

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Conclusions

• Hard Choices face us in the next 20 years
• Effective adaptive energy management can reduce
  heating energy requirements in a low energy
  building by 50 or more.
• Heavy weight buildings can be used to effectively
  control energy consumption
• Photovoltaic cells need to take account of
  intended use of electricity use in building to
  get the optimum value.
• Building scale CHP can reduce carbon emissions
  significantly
• Adsorption chilling should be included to ensure
  optimum utilisation of CHP plant, to reduce
  electricity demand, and allow increased
  generation of electricity locally.
• Promoting Awareness can result in up to 25
  savings
• The Future for UEA Biomass CHP? Wind Turbines?

"If you do not change direction, you may end up
where you are heading."
Lao Tzu (604-531 BC) Chinese Artist and Taoist
philosopher