Reducing energy demand at building and community level

Professor Rajat Guptargupta@brookes.ac.uk

Discussion meeting on Energy Demand Management and Reduction20 June 2011, RIBA, London

• Current UK policy for low-carbon domestic refurbishment • DECoRuM approach: Modelling and mapping large number of

dwellings rapidly on a house-by-house level • Measurement, Monitoring & Occupant feedback• TSB Retrofit for the future programme: case studies • Evaluating low carbon communities: EVALOC project• Key Conclusions

Structure of presentation

- 21 million homes that exist today will still be with us in 2050

- UK Government set target to transform over 400,000 dwellings/year by 2015; 7 million to be treated by 2020 and all by 2030. (Source : DECC-HESS)

- Households spent £1534 on alterations, improvements & repairs in 2008 and £1239 on energy. (Source: Office for National Statistics)

The low-carbon refurbishment context…

The existing stock is in a poor state

The majority of existing houses lie towards the bottom of the SAP scale.

Profile of Energy Performance in Existing Dwelling Stock, 20041

0% 20% 40% 60% 80% 100%0% 20% 40% 60% 80% 100%

pre 1919

1919-1944

1945-1964

1965-1974

1975-1980

1981-1990

post 1990

4.2 m

3.6 m

4.4 m

1.8 m

1.3 m

3.1 m

1.8 m

Dwellings

86+ 71 to 85 56 to 7041 to 55 21 to 40 1 to 20

SAP 2001 Levels[1] Based on English House Condition Survey (EHCS) 2004,

Key elements:

1. Large-scale

2. Whole-house

3. Cost-effective

4. RapidSuccess of such a low-carbon refurbishment approach requiresrapidly identifying individual properties which could benefit fromenergy efficiency measures, in addition to making citywide estimates.

The Low-carbon Refurbishment: a substantial challenge

Considers a household’s energy needs and CO2 impacts as a whole, and establishes a comprehensive package of

measures to address them, which also includes renewable energy measures where appropriate to the property

DECoRuM approach: Modelling and mapping energy use and CO2 reductions for a large number of dwellings rapidly on a house-by-house level

Distribution of CO2 emissions on a house-by-house level in Oxford

• A GIS-based domestic carbon-counting and carbon-reduction model• Bottom-up toolkit to help planners measure, model, map and reduce energy

use and carbon emissions, on a house-by-house level• Received the 2006 RIBA President’s medal for outstanding research

DECoRuM carbon mapping on an urban scale

DECoRuM CO2 reduction model: estimating solar potential

Estimating the solar potential of dwellings in Oxford

• Individual dwelling represented as the base level of resolution.

• Pollution hotspots can be spatially located and targeted for improvement.

• Assessment requires no access to the property.

• A robust data filtering process provides accurate and reliable results.

• Cost-benefits analysis enables cost comparison of different measures.

• Helps to estimate the potential for citywide application of solar energy systems.

• A useful visual aid when encouraging householders to install energy efficiency measures.

DECoRuM is being applied in SNACC, EVALOC, EPSRC heat pump projects as well as Counting the real carbon, TSB Retrofit for future projects.

DECoRuM: Key benefits

www.decorum-model.org.uk

From predictive modelling to building performance evaluation (BPE)

Measurement, Monitoring and Occupant feedback

• Very little hard evidence of actual housing performance.• Hard for designers to be objective about performance assessments and

user feedback - it can identify as much bad news as good.• Too many buildings that claim to be green aren’t.

Current situation with performance low-energy housing

Credibility gap exists between predicted and actual performance

Bills Total consumption (kWh)

Cost (£) Per unit area (kWh/m2)

Gas (29 Jan 08-28 Jan 09) 9465.16 336.05 123.08

Electricity (Lighting + fans/ pumps + appliances) 2481.00 354.15 32.26

Water use - 200.85 -

Total (energy only) 11,946.14 690.2 155.35

SAP model Total consumption (kWh)

Cost (£) Per unit area (kWh/m2)

Gas 24,139.14 393.45 313.5

Electricity (Lighting +fans/ pumps) 802.52 91.14 10.42

Total energy 24,941.66 484.5 323.92

• The theoretical potential of the base building’s fabric and services under standard assumptions.

• The build quality and commissioning of the above.• The fit out by the occupant. THIS CAN UNDERMINE THE DESIGN

INTENTIONS.• The equipment added by the occupant.• The pattern of use of the building & equipment.• Operation, control, maintenance, management of all the above, by

both landlord and tenant.

So, what makes up actual consumption?

Adapted from: Bill Bordass, 2005

• BPE involves systematic collection and evaluation ofinformation about the performance of a building in use both froma technical and occupants’ perspective.

• Key elements include:• Post-construction fabric testing• Energy assessment and benchmarking• Monitoring of environmental conditions• Occupant feedback survey

BPE is essential to verify actual CO2 reductions and discover unintended consequences

TSB Retrofit for the future programme

Phase 1: Design phase (September 2009 – November 2009)• Whole house low-carbon retrofit strategies that achieve 80% reduction in CO2 emissions and

energy consumption.• Pre-retrofit in-use monitoring and occupant feedback – to understand actual in-use

characteristics of the house and what occupants want, and identify user-centred solutions• SAP and PHPP-based modelling

Involved in three projects (each worth £20k) covering typical UK dwellings: 1. 19th century solid-wall end-terrace, Oxford2. 1945 mid-terrace with flat concrete roofs, Cumbria3. 1980’s terraced house, London

1 2

Retrofit for the Future programme: Phase 1

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Monitored temperature – 15 November 2009

1325 ppm

1395 ppm

1389 ppm

1309 ppm

1378 ppm

1250 ppm

1246 ppm

Phase 1: Using pre-retrofit monitoring and occupant feedback

Our adopted low-carbon retrofitting approach

• Fabric first improvement and then low carbon/zero carbon systems.• Reduce demand for energy by 60-75% using energy efficiency

measures. • Encourage a low-maintenance 'fit and forget' approach • User-centred solutions • Improve health, comfort and well-being of occupants:

Phase 2: (March 2010 - February 2013)• Installation of whole-house low-

carbon retrofitting packages• Detailed in-use whole-house

monitoring and post-occupancy evaluation for over two years post-refurbishment (2011-2013)

Phase 2: Implementation and monitoring

Innovative solutions

EVALOC: Evaluating the impacts, effectiveness and success of DECC-

funded low carbon communities on localised energy behaviours

Principal Investigator• Professor Rajat Gupta, Oxford Brookes University

Co-Investigators• Dr Nick Eyre, University of Oxford• Dr Karen Lucas, University of Oxford • Dr Sarah Darby, University of Oxford

Researchers• Jo Hamilton, Researcher, University of Oxford• Dr Caroline Fox, Research Fellow, Oxford Brookes University• Ruth Mayne, Researcher, University of Oxford

• Three-year research project funded by ESRC’s and EPSRC’s Energy andCommunities Collaborative Ventures (worth £6 million) supported by RCUKEnergy Research Programme

• One of 7 projects funded out of 86 submitted

• EVALOC received grant of £1.14million (Total project cost: £1.37 million)

• Runs from January 2011 to December 2013

• EVALOC brings together an interdisciplinary team of researchers from social science and building sciencebased disciplines from Oxford Brookes University and University of Oxford.

What is EVALOC?

• Evaluate six selected case study projects under the DECC’s Low Carbon Communities Challenge (LCCC) in terms of their:• IMPACTS (on changing

individual and community energy behaviours)

• EFFECTIVENESS (on achieving real-savings in energy use CO2emissions)

• SUCCESS (in bringing about sustained and systemic change).

• To assess, explain and communicatethe changes in energy use due to community activities within six selected case study communities.

What is EVALOC?

What questions are we trying to answer? • How can community-based organisations best monitor and

communicate their own effectiveness at energy demand reduction, and learn from their work? What are the limits and barriers?

• What are the effects and impacts of the LCCC interventions on behaviour change, energy use, and CO2 reductions, and how sustainable are they ?

• How useful is DECoRuM for communities and policy makers in measuring, tracking, visualising and communicating CO2 savings to communities?

• How are energy displays used in a social context, and how can they be used to best effect to raise awareness and change practices ?

• What is the role of social networks in promoting or suppressing the communication and take-up of new energy technologies, and how far do these interconnect with local community networks?

• What is the role of cross-learning within a broad ‘community of interest’, for energy-related change?

Conceptual frameworkEvaluating Low Carbon Communities

Impact Effectiveness Success

On localised energy behaviourOn achieving real-savings in

energy use and CO 2 emissions In bringing about systemic change

WORK PACKAGES

WP3b Identifying and mapping social and community networks

WP3b Identifying and mapping social and community networks

WP4 Knowledge exchange and transfer OUTPUTS

Open source toolkit Evaluation & community specific toolkits

Guide / report for metering and feedback technologies in community projects

WP1 Action research and capacity building in communities

WP2 Monitoring, Mapping andMeasurement

WP3a Communications, metering, feedback

GIS-based Community Energy Monitoring Toolkit

Action Research Toolkit

Detailed datasets of energy use, thermal environment & occupant feedback

Dissemination - Workshops, conferences

Mapped social and community networks - indentifying communication pathways for

energy discourses

• Energy modelling and spatial mapping provides a useful platform for rapid, large-scale and low-carbon retrofitting of UK housing.– Bringing together monitoring and mapping in EVALOC project

• Focus on whole-house retrofitting packages: explore room-by-room implementation to minimise disruption for occupants– Think of the user interface issues with new technologies. – Accounting for the increasing use of appliances by occupants

• Use BPE techniques to verify performance post-retrofitting (and pre-retrofitting) – Focus on ‘Need to know’ versus ‘nice to have’– Spot key problems rather than monitoring for the sake of it– Build intelligent feedback from monitoring - avoid information overload – Issues related to privacy

• KEEP IT SIMPLE, DO IT WELL AND THEN BE CLEVER (Dr Bill Bordass, Usable Buildings Trust)

Overall conclusions: lessons and challenges