حمل و نقل مسافر در نیجریه: تجزیه و تحلیل زیست محیطی و اقتصادی با توصیه های روشی
|کد مقاله||سال انتشار||مقاله انگلیسی||ترجمه فارسی||تعداد کلمات|
|29057||2013||9 صفحه PDF||سفارش دهید||6367 کلمه|
Publisher : Elsevier - Science Direct (الزویر - ساینس دایرکت)
Journal : Energy Policy, Volume 55, April 2013, Pages 353–361
This paper presents the life cycle environmental impacts and economic costs of the passenger transport sector in Nigeria for 2003–2030. Four scenarios are considered: business as usual (BAU); increased use of public transport (buses) at the expense of cars (LOWCAR) and motorcycles (LOWMC), respectively; and high economic growth with increased car ownership and decline of public transport (HICAR). The findings show that for the BAU scenario the life cycle environmental impacts double over the period, despite the assumption of increased fuel and vehicle efficiency of 35% over time. The total fuel costs at the sectoral level increase three times, from US$3.4 billion/yr in 2003 to US$9.7 billion in 2030. Increasing the use of buses would reduce the environmental impacts on average by 15–20% compared to BAU; at the same time, the total fuel costs would be 25–30% lower. If the use of cars grows much faster due to a high economic growth as in HICAR, the environmental impacts and fuel costs would increase by 16% and 26%, respectively. These results demonstrate clearly that future transport policy in Nigeria should promote and incentivise public (bus) transport as a much more environmentally and economically sustainable option than transport by cars and motorcycles.
The transport sector was globally responsible for 62% of world oil consumption and 25% of total final energy demand in 2011 (IEA, 2011). In Nigeria, the oil consumption by the transport sector is even greater, consuming 80% of the total petroleum products (IEA, 2008) and making it the largest consumer of fossil fuels in the country. Road transport dominates, accounting for over 90% of all transport in terms of kilometres travelled (FOS, 2004, CFA, 2005 and Oni, 2010). This is similar to the overall average for Africa, with road transport contributing to 80% and 90% of goods and passenger movements, respectively (UN, 2009). In Nigeria, this is due to a decline in other transport sectors, especially rail. For example, the number of rail passengers declined from 14 million to less than 1 million between 1980 and 2005 while rail freight decreased from 3 million tonnes to less than 500,000 tonnes within the same period (AfDB, 2007). This has led to an enormous pressure on the already inadequate and deteriorating road infrastructure in the country. For instance, only about 15% of the total 193,200 km of roads are paved (AfDB, 2006). The high consumption of petroleum products in Nigeria translates into the daily sales volumes of about 26 and 4.2 million litres of petrol and diesel, respectively (NNPC, 2008 and Mitchell et al., 2008). However, the four (Government-owned) refineries operate at about 40% of their capacity so that petroleum products have to be imported to supplement the demand (NNPC, 2006). For example, in 2005, the Government imported about 69% of the petrol and 43% of the diesel consumed in the country (NNPC, 2006). Given that all the fuel imports are paid for at international prices and are then subsidised for local affordability, this represents a significant drain on the country’s already stretched financial resources. The consumption of fossil fuels (mainly petrol and diesel) in the transport sector contributes 25.4 million tonnes of CO2 or 50% of the national emissions; almost all of this (99%) is from road transport (IEA, 2010). Gas flaring adds further CO2 emissions – this is a significant issue for Nigeria, since up to 75% of the gas extracted together with oil is flared (ERA, 2005 and Sonibare and Akeredolu, 2006). However, this amount is gradually reducing and gas flaring in Nigeria is set to end in the near future (Nzeshi, 2010). The huge dependence on road transport and a lack of an effective regulatory framework have also led to other societal concerns. Notably, the increase of motor vehicles from 1.3 million in 2000 to 2.2 million in 2004, representing an annual increase of about 17% (AfDB, 2006), has led to congestion in urban areas as well as increased noise and air pollution (Adegbulugbe et al., 2008), contributing to a wide range of health impacts (Krzyzanowski et al., 2005). The increase in road accidents is also a major concern; for example, an average of 18,387 cases of road accidents per year were reported between 2003 and 2007 with the number of fatalities averaging 8672 (NBS Nigeria, 2009). With a population of over 158 million people (IEA, 2011), depending heavily on fossil fuel based transport, it is important to understand fully the environmental and economic impacts of the current passenger transport sector in Nigeria as well as how these may change in the future as the sector develops. Therefore, this paper considers the life cycle environmental impacts and economic costs of the passenger transport sector over the period 2003–2030. For these purposes, scenario analysis is used to explore possible ways in which the sector could develop. In addition to ‘business as usual’, three further scenarios are considered: two are based on sustainable transport development promoting public transport by buses, with one assuming reduced use of cars and another decrease in the use of motorcycles; the final scenario assumes increased ownership and use of cars at the expense of public transport. While there are numerous studies of the passenger transportation sector in different parts of the world, they are rarely assessed on a life cycle basis and even if so, only energy use and greenhouse gas emissions are considered (e.g. Eriksson et al., 1996, Bouwman and Moll, 2002, McCollum and Yang, 2009, Chester et al., 2010, Ou et al., 2010, Akerman, 2011, Hao et al., 2011 and Croft McKenzie and Durango-Cohen, 2012). No such studies have been found in literature for Nigeria. Thus, as far as the authors are aware, this is the first life cycle assessment study of the passenger transport sector in Nigeria providing a full picture of the sector’s environmental impacts from ‘cradle to grave’, indicating ‘hot spots’ and opportunities for improvements over the whole life cycle. This is also the first study showing the trade-offs between the life cycle environmental impacts and economic costs for the sector, aiming to inform future transport policy in Nigeria. The paper is structured as follows: Section 2 provides a description of the current transport system as well as the scenarios considered; the results are presented in Section 3 and the conclusions and policy recommendations in Section 4.
نتیجه گیری انگلیسی
As shown in this work, if business as usual continues, passenger transport in Nigeria is set to double by 2030, leading to a substantial increase in the number of vehicles on the roads. This in turn would almost double the current life cycle environmental impacts from this sector, despite the anticipated improvements in fuel efficiency and vehicle technology. The total fuel costs would reach US$9.7 billion per year by 2030, up three times from US$3.4 billion in 2003. Therefore, there is a need to incorporate sustainability considerations as a priority in the future plans for the transport sector before irreversible changes are made. However, policy and infrastructure options are limited within the Nigerian context as the Government also faces other dilemmas in crafting policies that address multiple priorities in the provision of public service needs. These priorities include concentrated efforts in meeting electricity demand and addressing poverty and education concerns in the near future. Due to limited resources, these may compete with the need to invest in more sustainable development of passenger transport. However, measures such as promoting the use of public transport are within the grasp of the Nigerian Government. As also shown in this work, car transport accounts for most of the environmental impacts (on average 60%) and fuel costs (75%), so any measures to improve sustainability in this sector should target car transport as priority interventions. The results from this study show that bus transport is much more environmentally and economically sustainable than transport by cars and motorcycles. Thus, vigorous promotion and incentivisation of bus transport is likely to deliver beneficial outcomes, but this would require considerable policy dexterity and political audacity in a country where representative democracy is still in its early stages. For example, the Government could ban motorcycles (as it has done in some states for safety reasons), introduce taxes and levies on cars and provide more incentives for bus operators. More could also be done to improve further the sustainability of the sector by rebuilding, upgrading and expanding the railway infrastructure. Although this would require significant investments, railway transport is more sustainable than road transport and would therefore be a better long-term option. It has also been shown in this study that gas flaring contributes up to 15% of the life cycle environmental impacts from passenger transport. Ending gas flaring would not only reduce the environmental impacts but also contribute to the Government’s revenues from oil production. Perhaps more importantly, ending gas flaring along with other environmentally responsible interventions could deliver tangible outcomes to the communities in the Niger Delta whose livelihoods have been affected by gas flaring and other local contamination associated with oil extraction. Increased revenues from the sale of the this additional amount of gas can also be used to support economic and social development in the region. However, sustainability considerations in this sector should not only be limited to environmental and economic variables but broadened to address health and other social impacts. For example, increased number of vehicles on the roads will increase traffic and add significant pressure on road infrastructure. There are also increased health risks from pollution in addition to increased risks of accidents. Thus policy initiatives in the transport sector should aim to address these concerns as a priority.