A freight transport demand, energy and emission model with technological choices. ESRI Working Paper 669 June 2020.

Reducing energy consumption and emissions from freight transport plays an important role in climate change mitigation. However, there remains a need for enhanced policymaking and research to explore a low carbon future of freight transport. This research establishes a freight transport model to simulate transport demand (tonne kilometre), energy consumption and emissions. The model incorporates macroeconomic factors, policy indicators, technological characteristics, detailed profiles of the vehicle stock and travel distances, and behavioural parameters with discrete based choices. This model is applied to the freight transport sector in Ireland with scenarios running out to 2050. The results show that overall freight transport demand increases substantially from 2015 to 2050. Economy-wide climate policies (i.e. carbon tax) and high fuel prices result in modest reductions in energy consumption and CO2 emissions in freight transport, compared to a baseline. Sectoral measures, such as European CO2 emission performance standards, that aim to improve new vehicle fuel efficiency/emission rates can potentially lead to significant reductions, but such measures face a lag in greening the goods vehicle stock in the short/mid term, and uncertainties in policy compliance and technical barriers in the long run. Notably, in spite of few commercially mature vehicle technologies, adoption of biofuel and alternative freight vehicles are expected to bring additional reductions in future energy consumption and emissions. In all, for a transition to a low carbon future for freight transport, a comprehensive and dynamic policy agenda should be developed to promote low or zero emission vehicles, especially for heavy goods vehicles

Ex-post decomposition analysis of passenger car energy demand and associated CO2 emissions

This paper investigates, quantifies and ranks the factors influencing passenger cars energy demand and emissions. A vehicle stock-model approach is used for an ex-post decomposition analysis, based on administrative data, examining the impact seven underlying factors driving energy demand. The impact of methodological choice and model disaggregation are also explored. In light of the 2015 vehicle emissions scandal, the paper quantifies the difference between manufacturer-test vehicle performance and real world or â on-roadâ performance for a national stock model and determines the relative impact on passenger cars energy consumption. When examining the technical performance improvement, the choice of metric can lead to a distortion of 2.2 percentage points (14% overestimate) in the quantification of the efficiency improvement of the vehicle stock. The analysis pays particular attention to the influence of fuel or technology switching â which is often quoted as a factor influencing energy use and emissions but rarely quantified. Even when using litres per hundred-kilometre gasoline equivalent to measure the performance improvement, changes in the makeup of the stock can lead to distortion in the efficiency measure. The results of a full decomposition analysis highlight that technical performance improvements (energy efficiency improvements for the purpose of this paper), will not provide significant energy and emission savings when the impact on-road consumption is included. The paper concludes that technology switching in conjunction with policies targeting ownership and usage are the most effective measures to control passenger car energy consumption and associated CO2 emissions

Quantifying transport energy efficiency savings

The importance of quantifying energy savings and improvement in energy efficiency for each sector of the economy is now widely recognized in order to demonstrate progress towards targets and compliance with legal obligations. The focus of this paper is specifically on evaluating energy efficiency in transport using the ODEX methodology. More detailed data has recently become available on transport energy trends and the underlying factors that allow the authors improve the calculation of Ireland’s transport ODEX. Through data mining of administrative databases mileage, volume, age, engine type and size data are available at a disaggregated level for each mode of road transport. In particular this paper examines private car energy efficiency, quantifying the change arising from improved data. There was an overall slight improvement (0.71 percentage points) in the Irish private car ODEX when both proposed changes of using MJ/km as the unit consumption measure and modeling the stock by vintage were applied. The overall effect of the revised transport ODEX calculation does not show a significant increase in energy savings associated with the value of the ODEX indicator (0.82%). However the purpose was to improve the methodology of how the ODEX was being calculated, not necessarily increasing the savings

Recession or retrofit: An ex-post evaluation of Irish residential space heating trends

Analysis of the technical potential for energy efficiency often highlights very large potential savings; however, the reality of savings achieved often falls far short of this potential. Ex-post analysis is known to be important for quantifying realised energy-efficiency savings, but is often neglected for many reasons. This paper describes an approach to an ex-post analysis that uses readily available administrative data and provides insights into the impact of an energy-efficiency policy measure of residential energy-efficiency retrofitting (upgrades). Ex-post analyses have the advantage of including the impacts of events and behaviours that coincide with energy-efficiency programs and thus facilitate disentangling external influences and avoidance of misattribution of savings. Three different quantitative approaches are used to determine whether the national energy-efficiency retrofit programmes or the economic recession was responsible for the sharp fall in residential space-heating energy demand in Ireland between 2007 and 2012. The analysis finds that while Government energy-efficiency retrofitting programmes have played a role in reducing energy consumption, the biggest influence by far between 2007 and 2012 was the economic recession. The top down decomposition analysis recorded energy savings (including â savingsâ that were due to the recession) that were 3.9 times greater than bottom-up retrofit savings related to residential space-heating measures over the period 2006 â 2012. The analysis highlights that an important policy challenge is to achieve reduced consumption due to behavioural changes while experiencing economic growth

The Environmental Context and Function of Burnt-Mounds : New Studies of Irish Fulachtaí Fiadh

The authors acknowledge funding from The Leverhulme Trust (F/00144/AI) and assistance from a large number of individuals including; Margaret Gowen (access to sites and assistance throughout),A. Ames, H, Essex (pollen processing), S. Rouillard & R. Smith (illustrations), C. McDermott, S. Bergerbrandt, all the staff of Margaret Gowen & Co. Ltd, TVAS Ireland and CRDS. Excavation works and some post-excavation analysis was paid for my Bord Gáis and the National Roads Authority (now Transport Infrastructure Ireland). Thanks also to David Smith for access to the Maureen Girling collection and assistance with identifications.Peer reviewedPostprintPostprin

The environmental context and function of Burnt-Mounds: new studies of Irish Fulachtaí Fiadh

Burnt mounds, or fulachtaí fiadh as they are known in Ireland, are probably the most common prehistoric site type in Ireland and Britain. Typically Middle–Late Bronze Age in age (although both earlier and later examples are known), they are artefact-poor and rarely associated with settlements. The function of these sites has been much debated with the most commonly cited uses being for cooking, as steam baths or saunas, for brewing, tanning, or textile processing. A number of major infrastructural development schemes in Ireland in the years 2002–2007 revealed remarkable numbers of these mounds often associated with wood-lined troughs, many of which were extremely well-preserved. This afforded an opportunity to investigate them as landscape features using environmental techniques – specifically plant macrofossils and charcoal, pollen, beetles, and multi-element analyses. This paper summarises the results from eight sites from Ireland and compares them with burnt mound sites in Great Britain. The fulachtaí fiadh which are generally in clusters, are all groundwater-fed by springs, along floodplains and at the bases of slopes. The sites are associated with the clearance of wet woodland for fuel; most had evidence of nearby agriculture and all revealed low levels of grazing. Multi-element analysis at two sites revealed elevated heavy metal concentrations suggesting that off-site soil, ash or urine had been used in the trough. Overall the evidence suggests that the most likely function for these sites is textile production involving both cleaning and/or dyeing of wool and/or natural plant fibres and as a functionally related activity to hide cleaning and tanning. Whilst further research is clearly needed to confirm if fulachtaí fiadh are part of the ‘textile revolution’ we should also recognise their important role in the rapid deforestation of the wetter parts of primary woodland and the expansion of agriculture into marginal areas during the Irish and British Bronze Ages

Improving the quantitative evaluation of energy efficiency

This thesis considers the adage “what gets measured gets done” and postulates that understanding and improving how energy efficiency is measured can contribute to maximise the contribution of energy efficiency and assist in meeting energy and climate targets. This thesis addresses the research question of how to optimally quantitatively evaluate energy efficiency. The impact of fuel switching, different levels of data aggregation, and data availability and fluctuations on measuring energy efficiency is established through real-world ex-post analysis. The analysis demonstrates use of readily available data sources from existing administrative databases, such as energy balances, to achieve timelier, accurate, and reliable estimates of energy efficiency. The thesis is predominately a mathematical examination of Index Decomposition Analysis (IDA) methods, with a particular a focus on the Logarithmic Mean Divisia Index 1 (LMDI-1) methodology. Often perceived as difficult to understand, mathematical proofs and heuristics are included to aid with understanding, application and interpretation of the LMDI-I methodology. The thesis concludes that general choices of how a decomposition analysis method is applied may be more significant than the choice of IDA methodology. In particular, the choice of energy-efficiency indicator or metric and the level of disaggregation of the analysis, with disaggregation by fuel type or energy source key to improve estimates of the contribution of energy efficiency. Nevertheless, unique properties of the LMDI-I methodology contribute to making that the IDA methodology of choice. To prevent unrealistic expectations of what energy efficiency can achieve, the author also advocates the inclusion of as many explanatory factors as possible in IDA, to contextualise the contribution of energy efficiency in energy systems

Impacts of an emission based private car taxation policy - First year ex-post analysis

This paper assesses the impacts of a targeted policy designed to influence car purchasing trends towards lower CO2 emitting vehicles. Vehicle registration tax and annual motor tax rates in Ireland changed in July 2008 from being based on engine size to emissions performance of cars. This paper provides a one year ex-post analysis of the first year of the tax change, tracking the change in purchasing trends arising from the measure related to specific CO2 emissions, engine size and fuel, and the implications for car prices, CO2 emissions abatement, and revenue gathered. While engine efficiency improvements had been offset by purchasing trends towards larger and generally less efficient cars in the past, with the average MJ/km remaining constant from 2000 to 2007, this analysis shows that in the first year of the new taxation system the average specific emissions of new cars fell by 13% to 145 g/km. This was brought about, not by a reduction in engine size, but rather through a significant shift to diesel cars. Despite an unexpected reduction in car sales due to a recession in 2008, the policy measure has had a larger than anticipated impact on CO2 emissions, calculated to be 5.9 ktCO2 in the first year of the measure. The strong price signal did however result in a 33% reduction in tax revenue from VRT, in financial terms amounting to a drop of [euro]166 million compared to a baseline situation.Transport energy Private car CO2 emissions reduction Climate change policy Ex-post analysis Ireland