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3 Energy Demand and Related CO ₂ Emissions

The main end-use sectors are, in decreasing order of energy consumption: domestic, transport, industry and services:

Figure 1: Sectoral energy split

This section discusses energy demand in each sector and explains the assumptions underlying the calculations. Details of the analyses made to arrive at these figures are shown in the Appendices.

3.1 Domestic

3.1.1 Approach taken to estimating domestic energy demand

The energy consumption and fuel split figures for the domestic sector are based on DTI statistics ^10,11. These have been adjusted to take into account Scottish factors and this is discussed in greater detail in Appendix 1.

• Scottish population, compared with entire UK. In 2002, Scotland = 8.5% of UK total.
• The colder climate. Scotland typically has 10% more degree-days than the UK average and this affects the requirements for space heating.
• Although Scotland has roughly the same daylight hours as the rest of the UK, being further north means more of Scotland's hours of daylight occur at times ( e.g. early mornings in the summer) when they cannot be taken advantage of.
• The average SAP rating for Scottish homes is 46.5 and 51 for England and Wales. In addition there is evidence that more than double the number of homes in Scotland have little or no loft insulation, compared with England. Conversely, in Scotland approximately 38% of dwellings are flats, compared with only 20% in England. These points are reflected in the requirements for space heating.
• Gas is not readily available in some areas of Scotland ¹². For the Scottish Energy Study, a figure of 5-10% less access to mains gas compared with the UK average has been used ¹³.

The results for the domestic sector were cross-checked with the following data sources:

• The gas total and split across all demand sectors was in good agreement with data supplied by Transco (see section 5.2). Transco data also indicated that 75% of homes in Scotland have a supply of gas, which is in accordance with the assumption above.
• The electricity total was in good agreement with total electricity sales to public supplies (see section 4.1). Similarly, oil figures gave a reasonable match.

3.1.2 Results - demand in the domestic sector

Table 3 and Figure 2 show the breakdown of energy use by fuel. The dominant fuel used is gas, despite a significant proportion of Scotland not being connected to the gas mains.

Table 3: Headline figures for Scottish domestic energy consumption in 2002

Figure 2: Scottish domestic sector energy split

Comparing Scotland with the UK:

Table 4: Scottish v. UK domestic sector energy consumption in 2002

Energy used in the domestic sector in Scotland is 10.1% of the UK's total consumption in the domestic sector, however Scotland has 8.5% of the UK population.

The colder climate in Scotland will be a major factor behind this, as heating degree-days in Scotland are typically 10% more than the rest of the UK.

Scotland also has many hard-to-heat homes, but a higher proportion of the population live in flats, which require less energy. The fuel split was also different, with gas only slightly greater than the UK average (largely because of its limited availability in some regions), whereas all other fuels were considerably more than pro-rata.

The main fuels used in the domestic sector are gas, followed by electricity. Gas, along with coal and oil, is used for space and water heating and cooking. Typically, space and water heating account for over 80% of a household's energy consumption (although they are a smaller proportion of the energy bill, as electricity, which is more expensive, is used for much of the remaining demand).

Figure 3: Scotland and UK - domestic fuel split

Electricity has a large number of uses, including: lighting, powering kitchen and household appliances and computers, cooking plus some heating. Energy use by these appliances has increased substantially both as more appliances are bought and as the number of households increases.

Additional details of average dwelling occupancy, trends in ownership of domestic appliances and comparison between appliance ownership in Scotland and the UK as a whole are listed in Appendix 10.

3.2 Transport

The UK transport sector has shown continued year-on-year growth over the past 20 years or more, initially in road transport (both private car use and haulage) and more recently, air transport. The transport sector in Scotland mirrors the UK trends. There has been some flattening of demand for rail and marine transport, but these are both small in comparison to the amount of energy consumed by road and air and make only a modest impact on the figures.

3.2.1 Approach taken to estimating transport demand

The calculations for 2002 energy consumption by Scottish transport were based on:

• Initially, the principal source was DTI statistics for the UK. These data give usage for each of England & Wales, Scotland and Northern Ireland. Details are given in Appendix 4.
  A brief analysis of the statistics suggested that Scotland appeared to consume only 65-70% of the transport fuel per head of population compared with the UK average.
  Furthermore, Scottish transport energy consumption appeared to have been falling year-on-year since 1995.
  This seemed anomalous and contradicts data on the road mileage travelled in Scotland, which has risen year-on-year over the same period. In addition, Scottish transport statistics suggest that the vehicle km per head for Scotland is within 4% of the UK figure.

Table 5: Road traffic in Scotland compared with UK

• Further exploration revealed that this anomaly arose because for fuel sold by supermarkets, DTI attributed consumption to the supermarkets' headquarters, which are all in England. Hence, all supermarket sales are recorded as taking place in England, yet sales actually take place fairly evenly across the UK¹⁴.
• Rather than use DTI statistics, Scottish road energy consumption was instead calculated based on estimated km road journeys times "typical" km/litre fuel figures for different modes of transport, namely car - petrol, car - diesel, LGV, HGV, bus and motorbike. These revised calculations suggest that Scotland was responsible for 35.54 TWh of road transport energy and 8.69 Mt of CO ₂ emissions ¹⁵. More detail is given in Appendix 4.
• Estimations for marine and rail have been made from data from our transport team. As road and air dominate the transport energy figures, minor errors in these transport modes would not make a significant difference to the grand total:
• Air transport energy use in Scotland will be less than pro-rata UK population.
  Although there are several large airports in Scotland (and North Sea oil-field services), these are not the same size as the larger airports in England, especially around London.
  Air transport energy consumption figures have been calculated using the DTI statistics. These are based on deliveries of aviation fuel to Scottish airports. It is believed that this will not suffer from the same 'skew' as road transport ¹⁶.
  One needs to be aware that taken at face value, this analysis could be misinterpreted. Many long-haul passengers may start their journey in Scotland; but many are likely to start with a short-haul flight to (say) London or Europe, and then transfer to a long-haul flight. Only the first part of the total journey may be 'seen' and therefore attributed to Scotland.
  It has not been possible to estimate any 'downstream' consumption from these passengers, nor is it clear if and how the follow-on journeys should be treated and/or 'credited' to Scotland.
• Rail transport energy use was calculated based on Scotland/ UK pro-rata population.
• Marine energy use (ferries, container vessels etc.) was calculated as being greater than pro-rata UK population because there are numerous large ports in Scotland. A figure of double pro-rata was used.
• Finally, there is a small contribution from electricity to transport ¹⁷. Brief analysis suggests that Scotland is likely to be a little less than pro-rata UK (see Appendix 5) and it is estimated that Scotland transport accounts for 0.30 TWh of electricity.

Figure 4: Scottish transport sector energy split

The approximate split by different modes of transport is shown below:

The summary figures for transport are:

Table 6: Headline figures for Scottish transport energy consumption in 2002

Table 7: Scottish v. UK transport energy consumption in 2002

Details of how these were calculated are shown in Appendices 4 and 5. Scotland's contribution appears to be a little below pro-rata, partly because of air transport (discussed above) and partly because the UK statistics contain an element of unallocated energy consumption.

3.3 Industry

Scottish GDP has grown significantly in recent years, however, at the same time industrial consumption has seen a significant decline, with moves from manufacturing to service provision. This is illustrated by Figure 5 ¹⁹, which shows the changes in GDP in recent years for both services and manufacturing. This section describes the approach taken to estimate industrial energy use, and then goes on to look at the main energy-consuming sectors in Scotland in 2002.

Figure 5: Growth in GDP

3.3.1 Approach taken

For the purposes of this study we have distinguished between energy production (see sections 4 and 5) and industrial production: this section focuses on the latter.

The estimates of energy use in industry are based on the DTI statistics for total energy and fuel split for all industry and 14 key sub-sectors.

To assess energy consumption in Scottish industry the following steps were taken:

• For industrial sectors with large numbers of UK operators, the Scottish proportion was estimated based on the numbers of declared participants with Scottish addresses in Negotiated CCAs, as of 1 ^st April 2001, compared with the UK total. ²⁰
• Tailored adjustments were made for UK energy intensive sectors that had smaller numbers of large energy consumers, in particular, primary steel and aluminium, secondary steel and metals, mineral processing (cement, lime and glass), paper, chemicals (including petrochemicals).
• Adjustments were also made for the food and drink sector: Scotland comprising the vast majority of UK distilleries, a large and energy intensive sub-sector.
• Figures were compared and contrasted with the NAEI estimation of sector-split, from ' Greenhouse Gas Inventories for England, Scotland, Wales & NI, 1990-2002'. The comparison showed a reasonable match.

Details of the above calculations are included in Appendix 2.

Further information is also available on energy use in industrial sectors and can be obtained by considering data concerning sectors within the European Union Energy Trading Scheme ( EU- ETS). Details of the sectors included in phase 1 of the EU- ETS are given in Appendix 11.

3.3.2 Industrial demand results

Summary figures are:

Table 8: Headline figures for Scottish industry energy consumption in 2002

Figure 6: Scottish industry sector energy split

Comparing Scotland with the UK total:

Table 9: Scottish v. UK industry energy consumption in 2002

According to the analysis, Scottish industry energy consumption represents a similar amount per head as the UK, slightly less than pro-rata its UK population (8.5% of UK energy compared with 8.5% of the UK population).

Without doubt, this reflects changes to the general nature of UK industry over the past 10-15 years; the UK has moved away from energy-intensive sectors such as primary steel and metal refining and towards low-energy, high added value products and service industries. If anything, Scotland has shown even greater change, predominantly because of the large magnifying effect caused by the closure of the energy-intensive primary steel operation at Ravenscraig plus allied operations.

Electricity and gas dominate the sector's energy consumption, with oil and coal making much smaller contributions. Proportionally less coal is used in Scotland than in the UK as a whole.

Figure 7: Scotland & UK - industry fuel split

Energy use by the main industrial sectors in Scotland is shown below:

Figure 8: Scottish industry - main sectors

The main industry sectors are:

Food and Drink: a large and strategically important sector, comprising a number of sub-sectors. Scotland represents over 16% of the UK Food & Drink sector and dominates distilleries, with a significant proportion of UK maltsters, dairies and renderers.

Chemicals: another large, strategically important sector. There are several large chemical sites in Scotland, including those associated with the oil refinery at Grangemouth. Several of these generate their own electricity and heat via CHP.
Oil refining is discussed in section 4.2.

Engineering: a large sector that comprises a wide range of companies from some of the countries largest, to small, innovative companies.

Paper: Scotland accounts for over 20% of the UK paper industry (as of late 2001), comprising 16 of the 84 UK sites, of which seven were larger than 50,000 t capacity (out of a UK total of 36 sites), and accounting for one of the four integrated operations.

Plastics & Rubber: There is one major rubber manufacturing site, Michelin in Dundee, as well as many smaller companies in the plastics sector.

Mineral processing: not only quarrying/mining of hard stone and other quarry products, but also high temperature processing of minerals to make cement (one large site)

Textiles and leather tanneries: A traditional sector in Scotland with a particular focus on knitwear and furniture. While this sector has experienced significant competition and closures, there are 22,000 employed in textiles in Scotland.

Glass and ceramics: The glass sector includes two large container glass manufacturers, supplying the whisky sector and other drink producers, plus a glass insulation producer. There are no flat glass manufacturers in Scotland. In addition Scotland has a number of sites manufacturing crystal wares. The ceramics sector includes a number of brickmakers, refractory manufactures and producers of ceramic tableware.

Primary aluminium: Alcan Lochaber is the smallest of the three primary smelters in the UK. Nonetheless, it constitutes a large, energy-intensive facility that autogenerates the majority of its own electricity using hydro-generators. There are also some secondary (re-melt) aluminium operators.

Steel and other metals: these sectors have shrunk, primarily as a result of the closure of the Ravenscraig (primary, integrated) steelworks in the early 1990s together with the closure of allied/downstream and service industries.

Further details of energy use by sector and by process are given in the spreadsheet comprising Volume 3.

3.4 Service Sector

The service sector is the smallest of the four main Scottish demand sectors. As with the domestic sector, gas and electricity dominate the energy supply; given the nature of this sector and its activities, this split is not too surprising - electricity being used for the ever-increasing demand from PCs and other office equipment (along with some air-conditioning), whilst gas is used predominantly for space and water heating.

The service sector covers:

• Commercial buildings, including non-residential buildings, offices, banks, call centres, shops/retail and warehousing, etc.
• Public sector: offices and government/public buildings, hospitals and nursing homes, universities, colleges and schools, etc.
• Agriculture: including farms and forestry. This is a small sector but overlaps with industry's food & drink sector.

3.4.1 Service sector: approach to estimating demand

The service sector's consumption and fuel split was estimated:

• Total consumption was based on DTI statistics for total energy and fuel split for (1) entire industry and (2) split into appropriate sub-sectors.
• UK agriculture total was determined from DTI statistics for all services including agriculture minus a parallel BRE assessment of services excluding agriculture.
• The Scottish proportion of UK agriculture was based on the proportion of Scottish food & drink facilities in CCA compared with the UK total.
• All agriculture across the UK, including Scotland, was estimated to have only 70% access to gas, but greater access to wood/renewable heating.

For the commercial and public sectors, the Scottish percentage of the UK total has been estimated based on:

• Starting with pro-rata population - 8.5% of UK - as the default position.
• Adjustment (up) for the public sector, based on the fact that Scotland receives greater than pro-rata population public sector funding (according to the Barnett formula: Scotland receives 10% of UK public sector funding).
• Scottish commercial and public sectors are believed to have similar access to gas - as most of these buildings will be in larger cities/towns rather than rural.
• The colder climate. Scotland typically has 10-20% more degree-days than UK average. For 2002, this figure was calculated to be 18.9%. This will affect the requirements for space heating - as per the domestic sector.
• Building stock for the commercial and public sectors is believed likely to be similar to the rest of the UK (unlike the domestic sector).
• Scotland has fewer 'useful' daylight hours, therefore there is a greater need for electric lighting in Scotland, especially in winter.

Details of how these figures were calculated are shown in Appendix 3.

3.4.2 Service sector: results

Summary energy figures were:

Table 10: Headline figures for Scottish 'services' energy consumption in 2002

Figure 9: Scottish services sector energy split

Comparing Scotland with the UK total:

Table 11: Scottish v. UK services energy consumption in 2002

Figure 10: Scotland & UK - Service sector fuel split

Scotland's service sector consumes greater than pro-rata UK population across all fuel types. Again, this is not surprising, given that the public sector is slightly larger than the population pro-rata, the agriculture and forestry sector is much larger, and Scotland suffers a colder climate with fewer useful daylight hours.

The service industry is recognised as being a growth area for employment in the UK, increasingly replacing industry jobs. As such, consumption would be expected to rise.

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