11. GREENHOUSE GAS EMISSIONS
11. GREENHOUSE GAS EMISSIONS
11.1 In 2009, Scottish emissions of the basket of six greenhouse gases63 were estimated to be 51.0 million tonnes carbon dioxide equivalent (Mt CO2e). This is 7.0 per cent lower than the 2008 figure of 54.8 Mt CO2e. Between 1990 and 2009, there was a 28.9 per cent reduction in emissions. Transport emissions were 10.74 Mt CO2e in 2009, just under one fifth of total greenhouse gas emissions in Scotland. Of this, road transport is the largest component. Road traffic has increased steadily since 1996, and in 2010 was more than double the volume in 198364. Emissions from Scottish ferries have been estimated as between 0.2265 -0.2366 Mt CO2e.
11.2 Scotland is committed to reducing its greenhouse gas emissions by 80 per cent by 2050, with an interim reduction target of 42 per cent by 202067 . High-level measures for the delivery of these targets are identified in the Scottish Government's Climate Change Delivery Plan and in the Low Carbon Scotland Report on Policies and Proposals. Both set out an aspiration to reduce emissions from maritime transport by up to 20% by 2020.
11.3 Greenhouse gas emissions from vessel engines show an exact correlation between speed and CO2 and NOx emissions. For example, for a Type E vessel (i.e. a large ROPAX ferry) a reduction of 0.5 knots would result in some 20% less CO2 being produced68. A 0.5 knot reduction in vessel speed has been estimated to add approximately five minutes to a two hour journey.
11.4 The Scottish Ferries Review Consultation sought to elicit views on environmental issues, with a focus on the mitigation of climate change through reduction of greenhouse gas emissions. Two key approaches to achieving reductions in greenhouse gas emissions from ferries have been identified by the Scottish Government: technological measures; and demand and fleet management.69 The consultation sought views on how emissions from ferries could be reduced, and in particular sought views from operators and passengers as to whether they would support reductions in vessel speeds as a means of reducing emissions.
11.5 A range of suggestions was offered on how to reduce emissions from ferries. Overall the emphasis was on technical solutions, particularly for inclusion in new vessels, but service changes were also mentioned. In general the consultees did not support reductions in vessel speeds.
11.6 The proposals in the Draft Ferries Plan to extend the operating day and add additional services to routes are likely to result in an increase in the number of vessel movements. Additional services will mean increased fuel consumption across the ferry network, and therefore an increase in greenhouse gas emissions. At this stage it is not possible to quantify this increase. In addition, as the existing fleet ages, engines will become less efficient, which will also increase greenhouse gas emissions.
11.7 Chapter 4 noted the potential for an increase in emissions from vehicles as a result of increased passenger numbers encouraged by the roll out of RET across the ferries network. These will include greenhouse gas emissions. As with vessels, at this stage it is not possible to quantify this increase.
11.8 Mitigation of greenhouse gas emissions from ferries will be undertaken in the long-term through the Scottish Government continuing its current work in progressing fuel-efficiency measures, both in the design and procurement of new vessels70 and in supporting technology retrofit, for example, more efficient propulsion systems. The Scottish Government does not propose to impose emission reductions through the operation of vessels, e.g. reducing vessel speed.
11.9 It is likely that ferry operators will continue to implement fuel-efficiency measures as the price of fuel continues to rise. These include, for example, the use of anti-fouling paint which acts to reduce friction and increase fuel efficiency. (Biofouling of hulls can increase friction and thus require extra effort to achieve desired speeds. This therefore increases fuel consumption and in turn emissions of greenhouse gases. For example, a small amount of fouling can lead to an increase in fuel consumption by up to 40% due to the increased friction71. Anti-fouling paints can be used to prevent marine organisms from attaching themselves to the vessel hull.)
11.10 Measures to reduce greenhouse gas emissions from cars would be similar to those proposed in Chapter 4, i.e. through encouraging journeys by public transport. The Scottish Government is encouraging the integration of ferry timetables with those for public transport (i.e. bus and rail), through the current Northern Isles tender and the next CHFS tender.
11.11 The Scottish Government will explore with ferry operators, statutory advisers and others if there are additional measures for the mitigation of greenhouse gas emissions and the feasibility of progressing these, for example, the provision of onshore power supplies for vessels once in harbour. An update will be provided in the final Ferries Plan.