Our property teams and managing agents have been recording energy and water information on our extranet, the Portal. In each area we compare performance to the previous year and to our 2004/05 baseline.

All resource use figures are calculated according to the Department for Environment, Food and Rural Affairs (DEFRA) 2007 guidelines for companies’ environmental reporting. For reporting of carbon dioxide (CO₂) emissions related to energy use these guidelines require use of different carbon conversion factors to those used in previous years. To report year on year changes in CO₂ emissions all previously reported figures have been re-calculated using the new conversion factors.

Reporting performance on a year on year basis is not straightforward as portfolio composition can change significantly. Set out below is a table which shows that although the number of properties managed has declined by 33% over the last four years (from 2004/05) the floor areas of the common parts have increased by 96%.

	2007/08	2006/07	2005/06	2004/05
Total number of properties	64	61	96	94
Total number of properties reporting resource use	57	55	82	85
Percentage of properties reporting resource use	89%	90%	85%	90%
Total floor area (m²)	2,059,184	1,436,065	1,487,947	1,050,000
	2007/08	2006/07	2005/06	2004/05
% change in number of properties from 2004/05	-32%	-35%	2%
% change in no. of properties reporting resource use from 2004/05	-33%	-35%	-43%
% change in total floor from 2004/05	96%	37%	42%

The type of resource use reported varied, reflecting the variety of services provided in those common parts floor area. Most properties reported electricity use, fewer properties used water and gas, and no properties reported use of oil:

• 57 properties reported electricity data
• 19 properties reported gas data
• 0 properties reported oil data
• 21 properties reported water data.

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Total energy use and carbon emissions

Total consumption of energy (electricity, gas and oil) and use per m² reduced in 2007/08. Associated carbon dioxide (CO₂) emissions also decreased.

The 21% decrease in total consumption of energy since 2004/05 and use per m² largely reflects year-on-year reductions in reported resource use by properties as well as year-on-year changes in the composition of our property portfolio.

Electricity use decreased by nearly 8% between 2007/08 and 2006/07. In 2007/08 electricity use accounted for over 86% of the total CO₂ emissions from our property portfolio, and was our most intensive source of CO₂ emissions per m². The intensity of electricity use per m² also decreased from 28 kWh/m² in 2006/07 to 16 kWh/m² in 2007/08, largely due to the sale of one Distribution and Industrial property. This is consistent with previous years. During 2007/08 several managed properties procured Climate Change Levy exempt sources of electricity representing 14,683 tonnes of CO₂, just over 64% of the total reported CO₂ emissions.

Gas use increased by nearly 8% in 2007/08 from 2006/07, although it decreased by over 31% compared to 2005/06. The overall decrease since 2005/06 relates to a reported 58% decrease by three shopping centres and 39% decrease at five offices. In 2007/08 gas accounted for 14% of our portfolio’s CO₂ emissions and was our most intensively used resource on a kWh per m² basis. This has changed from last year when electricity was the most intensively used resource per m². This change was due to an increase in the reported floor area of retail park properties, whilst electricity use for the same property type has deceased.

None of our properties reported oil use during 2007/08 or 2006/07.

Properties sold and newly managed in 2007/08 are included in the data, and accounted for 0.08% and 11.68% respectively of total reported CO₂ emissions. Properties sold in 2006/07 are also included in the data and accounted for 6.34% of CO₂ emissions. The newly managed property in 2006/07 did not report data.

Figures 1 and 2 show energy use and associated CO₂ emissions, as a total and on a square metre (m²) basis for the different energy types for the period April 2006 to March 2008.

Figure 1 Annual energy consumption

Figure 2 Annual CO₂ emissions

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Average energy use by property type

We calculate average energy use (electricity and gas) by dividing total energy use by floor area (kWh/m²) for each property type. This standardised value indicates differences in intensity of energy use between property types.

In 2007/08 office properties used electricity most intensely on a m² basis compared with other property types (Figure 3). This has changed from 2006/07 when distribution and industrial properties used electricity most intensively. The intensity of use in distribution and industrial properties reduced primarily due to the sale in 2007/08 of a property that had particularly high and intense electrical use.

Shopping centres reported a large increase in intensity of electricity use from 67.75kWh/m² in 2006/07 to 148.98kWh/m² in 2007/08. This can largely be attributed to changes in our portfolio.

Offices reported a 10% increase in intensity of electricity use, from 136.71kWh/m² in 2006/07 to 150.92kWh m² in 2007/08. Again this can be attributed to changes in our portfolio.

There were no high street properties in our managed portfolio in 2007/08. However, in 2006/07 there was one managed high street property that reported a large decrease in intensity of electricity use from 2005/06. The accuracy of data for this property for 2005/06 was queried in the 2006 Corporate Responsibility Report.

Figure 3 Average electricity consumption per property type (kWh/m²)

In 2007/08 offices continued to use gas most intensely on a m² basis compared with other property types (Figure 4).

The intensity of gas use at offices increased from 104.69kWh/m² in 2006/07 to 163.23kWh/m² in 2007/08. This was due to changes in our office portfolio, with the sale of two properties in 2006/07, the addition of one property reporting gas use for the first time, and the majority of properties reporting higher gas use.

The intensity of gas use also increased across shopping centres and retail parks. The rise in intensity for retail parks was associated with changes in the reported floor area for the property type along with the high intensity of resource for a single property that was new to our portfolio this year. The increase in shopping centres was also due to changes in our portfolio for this property type.

Figure 4 Average gas use per property type (kWh/m²)

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Average carbon emissions by property type

There was an overall reduction of 1,398 tonnes of CO₂ in 2007/08, (5.78%) compared to 2006/07.

Offices, shopping centres and retail parks were the primary contributors in 2007/08 for both gas and electricity CO₂ emissions. The majority of the overall reduction was due to shopping centres reporting reduced CO₂ emissions of 3,709 tonnes in 2007/08 from 2006/07. This reduction was balanced by an increase in reported CO₂ emissions for retail parks of 2,945 tonnes in the same period.

Shopping centres reduced CO₂ emissions related to electricity by 3,744 tonnes, but increased CO₂ emissions related to gas by 35 tonnes, giving a net decrease of 3,709 tonnes. This decrease was primarily due to three shopping centres reporting reduced electricity use and associated emissions, and the number of shopping centres in our portfolio reducing to four in 2007/08 from nine in 2006/07.

Retail parks increased CO² emissions related to electricity by 3,009 tonnes, but decreased CO² emissions related to gas by 64 tonnes, giving a net increase of 2,945 tonnes. This increase was mainly due to the number of properties increasing to 36 in 2007/08 from 20 in 2006/07.

Offices remain the most intense producers of CO₂ emissions on a per m² basis; this has increased slightly from 74.61kg CO₂/m² last year to 79.94kg CO₂/m² this year. This increase in intensity is largely due to changes in our portfolio for this property type.

The largest increase in intensity of CO₂ emissions per m² occurred across shopping centres. In 2007/08 average intensity was reported as 82.46kg CO₂/m² compared to 27.06kg CO₂/m² in 2006/07. This increase is largely due to changes in our portfolio for this property type.

Offices contributed 44% of total CO² emissions, shopping centres 37%, and retail parks 18% for 2007/08 (Figure 3).

We use information on average CO₂ emissions per m² by property type in our ongoing energy benchmarking programme (Figure 4). Understanding how intensively energy is consumed per m² for each property type, helps us to prioritise energy reduction initiatives.

Figure 5 CO₂ emissions per property type (tonnes/year)

Figure 6 CO₂ emissions per property type (kg per m²)

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Total water use

Total water use increased by 5% in 2007/08 compared with 2006/07.

This increase was due to changes in our portfolio with the number of retail parks reporting water use increasing from three to seven, with an associated increase of 46,000m³. This increase was balanced by decreases in water use by all other property types.

Between 2004/05 and 2007/08 there was an overall decrease of nearly 26%. This decrease largely reflects a reported reduction in water use by properties that have installed water efficient technologies including rainwater harvesting tanks.

For 2007/08 sold properties accounted for 0.03% of total water use and newly managed properties 16.14%.

Figure 7 Annual water use (m³)

65% of our total water usage for 2007/08 is in offices, with retail parks and shopping centres consuming 18% and 17% respectively (Figure 8). This compares to data for 2006/07 of 73% for offices, 21% for shopping centres and 5.8% for retail parks.

Figure 8 Total water use per property type (m³)

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Average water use by property type

We calculate average water use by dividing total water use by floor area (m³/m²) for each property type. This standardised value indicates differences in intensity of water use between property types.

Overall intensity of water usage has decreased from 0.44 m³/m² in 2006/07 to 0.36m³/m² in 2007/08.

Offices were the most intense users of water on a m² basis in 2007/08 and 2006/07. This has changed from 2005/06 when residential properties were the most intense users. This difference is due to the sale of our residential property portfolio in the 2005/06.

Average water use intensity in 2007/08 has slightly increased in offices and shopping centres compared to 2006/07. For offices this average increase is due to the sale in 2006/07 of two properties that were low intensity users. Office properties included in the dataset in both years reported reductions in intensity of use. For shopping centres this average increase reflects only one property being included in the 2007/08 dataset. The intensity of use of this shopping centre is lower in 2007/08 compared to 2006/07.

Figure 9 Average water use per property type (m³/m²)

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