Intermittent Metrical

Thomas (Tom) Longden

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Proud to be a first-in-family university graduate, now working in academic research.

Currently I am at the Urban Transformations Research Centre at Western Sydney University.

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Research Themes

Research on prepayment for electricity in Australia, as well as prepayment for gas England and Wales.

Longden, T., Mellor, L., Davis, V. N., Foster, D., Johns, C., Klerck, M., McDinny, S., Taylor, A., Dwyer, A., Pigram, L., Thorburn, K., Beaton, C., Lester, K., Wingfield, G., Schreiber, B., Williams, N., Doughboy, C., Jack-Tayley, N., Nandy, A., … White, L. (2025). The Right to Power: Keeping First Nations’ Communities on Prepayment Connected. Original Power.

Longden, T. (2025). Temperature-related energy insecurity and heating degree thresholds for prepayment gas customers in England and Wales. Energy Economics, 108678.

Longden, T.,Quilty, S., Riley, B., White, L.V., Klerck, M., Davis, V., Frank, N. (2022). Temperature extremes exacerbate energy insecurity for Indigenous communities in remote Australia. Nature Energy, 7: 11-12.

Riley, B., Klerck, M., Markham, F., Longden, T., Napaltjari-Davis, V., Quilty, S., & Frank-Jupurrurla, J. (2025). The prepay “poverty premium”: Perspective on Australia’s Northern Territory prepayment tariff. Energy Research & Social Science, 127, 104189.

Riley, B., White, L. V., Wilson, S., Klerck, M., Napaltjari-Davis, V., Quilty, S., Longden, T., Jupurrurla, N.F., & Harrington, M. (2023). Disconnected during disruption: Energy insecurity of Indigenous Australian prepay customers during the COVID-19 pandemic. Energy Research & Social Science, 99, 103049. [Journal article]

Riley, B., White, L. V., Quilty, S., Longden, T., Frank-Jupurrurla, N., Morton Nabanunga, S., & Wilson, S. (2023). Connected: rooftop solar, prepay and reducing energy insecurity in remote Australia. Australian Geographer, 1-22.

Longden, T., Quilty, S., Riley, B., White, L.V., Klerck, M., Davis, V., Frank, N. (2022). Energy insecurity during temperature extremes in remote Australia. Nature Energy, 7: 43-54.

Research on the dangers of extreme heat, including the first study to use the national Australian Cause of Death Unit Record File.

Longden, T. (2025) Underestimating heat-related mortality—a comparison of excess mortality and death record studies for Australia, The Lancet Regional Health – Western Pacific, Volume 58.

Longden, T., Kompas, T., Norman, R., & Vardoulakis, S. (2022). Considering health damages and co-benefits in climate change policy assessment. The Lancet Planetary Health, 6(9), e712-e713.

Longden, T., Quilty, S., Haywood, P., Hunter, A., & Gruen, R. (2020). Heat-related mortality: an urgent need to recognise and record. The Lancet Planetary Health, 4(5), e171.

Longden, T. (2019). The impact of temperature on mortality across different climate zones. Climatic Change, 157(2), 221-242.

van der Linden, N., Longden, T., Richards, J. R., Khursheed, M., Goddijn, W. M., Van Veelen, M. J., … & van der Linden, M. C. (2019). The use of an ‘acclimatisation’ heatwave measure to compare temperature-related demand for emergency services in Australia, Botswana, Netherlands, Pakistan, and USA. PloS one, 14(3), e0214242.

Longden, T. (2019) Temperature-related mortality in Australia and the implications for climate change futures, The Lancet Planetary Health, Vol. 3, No. 3: e121.

Longden, T. (2018) Measuring temperature-related mortality using endogenously determined thresholds, Climatic Change, Vol. 150, No. 3-4: 343-375.

Various studies looking at policies or having notable relevance for policy change. This includes the Cheaper Home Batteries program, legacy solar feed-in-tariffs, renewable project lead-times, and the risk of property loss during a bushfire.

Longden, T., & Das, D. (2026). Changing the game: fast mover advantage in household solar and battery programs.

Longden, T. (2025). Temperature-related energy insecurity and heating degree thresholds for prepayment gas customers in England and Wales. Energy Economics, 108678.

Clapin, L., & Longden, T. (2024). Waiting to generate: An analysis of onshore wind and solar PV project development lead-times in Australia. Energy Economics, 131, 107337.

Callaghan, C.T., Benson, I., Major, R.E., Martin, J.M., Longden, T. and Kingsford, R.T., (2020). Birds are valuable: the case of vagrants. Journal of Ecotourism, 19(1), pp.82-92.

Keighley, T., Longden, T., Mathew, S., & Trück, S. (2018). Quantifying catastrophic and climate impacted hazards based on local expert opinions, Journal of Environmental Management, Vol 205: 262-273.

While at UTS I was a co-lead who secured funding from Sustainability Victoria for the evaluation of the Victorian Healthy Homes Program. This was a research partnership between the Centre for Health Economics Research and Evaluation (CHERE) and the UTS Institute for Sustainable Futures.

Page, K., Hossain, L., Liu, D., Kim, Y.H., Wilmot, K., Kenny, P., Campbell, M., Cumming, T., Kelly, S., Longden, T., van Gool, K. & Viney, R. (2025). Outcomes from the Victorian Healthy Homes Program: a randomised control trial of home energy upgrades. British Medical Journal Open, 15(2), e082340.

Campbell, M., Page, K., Longden, T., et al. (2022) Evaluation of the Victorian Healthy Homes Program: protocol for a randomised controlled trial, British Medical Journal Open.

Works on techno-economic analysis have included studies of hydrogen, offshore wind, and EV ready apartments.

Longden, T., Gatarin, G., Hellany, A., Leditschke, A., Kuch, D., Morrison, G., & Morrison, N. (2024). Driving change by supporting electric vehicle ready apartments. (APPI Policy Insights Paper). Australian Public Policy Institute.

Longden, T., Beck, F. J., Jotzo, F., Andrews, R., & Prasad, M. (2022). ‘Clean’ hydrogen? – Comparing the emissions and costs of fossil fuel versus renewable electricity based hydrogen. Applied Energy, 306, 118145.

Fazeli, R., Longden, T., & Beck, F. J. (2025). Dynamics of price-based competition between blue and green hydrogen with net zero emissions targets. Renewable and Sustainable Energy Reviews, 210, 115244.

Hughes, L., & Longden, T. (2024). Offshore wind power in the Asia-Pacific: Expert elicitation on costs and policies. Energy Policy, 184, 113842.

Hughes, L., Cheng, W., Do, T.N., Gao, A.M.Z., Gosens, J., Kim, S.Y. and Longden, T., 2024. Governing offshore wind: is an ‘Asia-Pacific Model’ emerging?. Climate Policy, pp.1-11.

Ueckerdt, F., Verpoort, P. C., Anantharaman, R., Bauer, C., Beck, F., Longden, T., & Roussanaly, S. (2024). On the cost competitiveness of blue and green hydrogen. Joule, 8(1), 104-128.

Sharma, A., Longden, T., Catchpole, K., & Beck, F. J. (2023). Comparative techno-economic analysis of different PV-assisted direct solar hydrogen generation systems. Energy & Environmental Science, 16(10), 4486-4501.

Wang, C., Walsh, S. D., Longden, T., Palmer, G., Lutalo, I., & Dargaville, R. (2023). Optimising renewable generation configurations of off-grid green ammonia production systems considering Haber-Bosch flexibility. Energy Conversion and Management, 280, 116790.

Webb, J., Longden, T., Boulaire, F., Gono, M., & Wilson, C. (2023). The application of green finance to the production of blue and green hydrogen: A comparative study. Renewable Energy, 219, 119236.

Studies of decarbonisation and sectoral transitions have focused on economy-wide, energy sector and transport sector changes.

Clarke, L., Jiang, K., Akimoto, K., Babiker, M., Blanford, G., Fisher-Vanden, K., Hourcade, J.-C., Krey, V. , Kriegler, E., Löschel, A., McCollum, D., Paltsev, S., Rose, S., Shukla, P.R., Tavoni, M., van der Zwaan, B., & van Vuuren, D.P. (2014). Chapter 6 – Assessing transformation pathways. In: Climate Change 2014: Mitigation of Climate Change. IPCC Working Group III Contribution to AR5. Cambridge University Press.

Meza, Maria Josefina Figueroa, Lew Fulton, Shigeki Kobayashi, Alan McKinnon, Peter Newman, Minggao Ouyang, James Jay Schauer et al. Chapter: 8 Title: Transport. (2014). In: Climate Change 2014: Mitigation of Climate Change. IPCC Working Group III Contribution to AR5. Cambridge University Press.

Carraro, C., Tavoni, M., Longden, T., Marangoni, G. (2017). The Potential Role of Gas in Decarbonizing Europe: A Quantitative Assessment. In: Hafner, M., Tagliapietra, S. (eds) The European Gas Markets. Palgrave Macmillan, Cham.

Longden, T., & Sferra, F. (2014). A Focus on the Latest Developments in the Modelling of Mitigation Options. In Climate Change Mitigation, Technological Innovation and Adaptation, Edward Elgar, 164-184.

Kriegler, E., Riahi, K., Bauer, N., Schwanitz, V. J., Petermann, N., Bosetti, V., Marcucci, A., Otto, S., Paroussos, L., Rao-Skirbekk, S., Currás, T. A., Ashina, S., Bollen, J., Eom, J., Hamdi-Cherif, M., Longden, T., Kitous, A., Méjean, A., Sano, F., Schaeffer, M., Wada, K., Capros, P., van Vuuren, D. P., Edenhofer, O., Bertram, C., Bibas, R., Edmonds, J., Johnson, N., Krey, V., Luderer, G., McCollum, D. and Jiang, K. (2015) A short note on integrated assessment modeling approaches: Rejoinder to the review of “Making or breaking climate targets—The AMPERE study on staged accession scenarios for climate policy”, Technological Forecasting and Social Change, Vol. 99: 273-276.

Longden, T. (2022). How renewables are transforming electricity grids: an analysis of Australia’s integrated system plan. Journal of Mega Infrastructure & Sustainable Development, 1-11.

Carrara, S. & Longden, T. (2017) Freight futures: the potential impact of road freight on climate policy, Transportation Research Part D: Transport and Environment, Vol. 55: 359-372.

Longden, T. (2014) Travel intensity and climate policy: the influence of different mobility futures on the diffusion of battery integrated vehicles, Energy Policy, Vol. 72: 219-234.

Bosetti, V. and Longden, T. (2013) Light duty vehicle transportation and global climate policy: the importance of electric drive vehicles, Energy Policy, Vol. 58, July: 209-219.

Pietzcker, R., Longden, T., Chen, W., Fu, S., Kriegler, E., Kyle, P. and Luderer, G. (2014) Long-term transport energy demand and climate policy: Alternative visions on transport decarbonization in energy-economy models, Energy, Vol. 64, 1, January: 95-108.

Schwanitz, V.J., Longden, T., Knopf, B. and Capros, P. (2015) The implications of initiating immediate climate change mitigation – A potential for co-benefits?, Technological Forecasting and Social Change, Vol. 90, A, January: 166-177.

Eom, J., Edmonds, J., Krey, V., Johnson, N., Longden, T., Luderer, G. Riahi, K. and van Vuuren, D.P. (2015) The impact of near-term climate policy choices on technology and emission transition pathways, Technological Forecasting and Social Change, Vol. 90, A, January: 73-88.

Riahi, K., Kriegler, E., Johnson, N., Bertram, C., den Elzen, M., Eom, J., Schaeffer, M., Edmonds, J., Isaac, M.,  Krey, V., Longden, T., Luderer, G., Méjean, A., McCollum, D.L., Mima, S., Turton, H., van Vuuren, D.P., Wada, K., Bosetti, V., Capros, P., Criqui, P. and Kainuma, M. (2015) Locked into Copenhagen Pledges—Implications of short-term emission targets for the cost and feasibility of long-term climate goals, Technological Forecasting and Social Change, Vol. 90, A, January: 8-23.

Kriegler, E., Riahi, K., Bauer, N., Schwanitz, V.J., Petermann, N., Bosetti, V., Marcucci, A., Otto, S., Paroussos, L., Rao, S., Curras, T. A., Ashina, S., Bollen, J., Eom, J., Hamdi-Cherif, M., Longden, T., Kitous, A., Méjean, A., Sano, F., Schaeffer, M., Wada, K., Capros, P., van Vuuren, D.P. and Edenhofer, O. (2015) Making or breaking climate targets: The AMPERE study on staged accession scenarios for climate policy, Technological Forecasting and Social Change, Vol. 90, A, January: 24-44.

Work on health has used linked data sets and time-series data to understand early withdrawal of retirement savings after a severe health shock and after‐hours primary care services.

Longden, T., & Naghsh-Nejad, M. (2025). Early Withdrawal of Retirement Savings After a Severe Health Shock: Evidence from Linked Administrative Data.

Longden, T., Hall J., van Gool K. (2018) Supplier‐induced demand for urgent after‐hours primary care services, Health Economics, Vol. 27, No. 10: 1594-1608.

Longden, T., Wong, C.Y., Haywood, P., Hall, J., van Gool, K. (2018). The prevalence of persistence and related health status: An analysis of persistently high healthcare costs in the short term and medium term, Social Science & Medicine, Vol 211: 147-156.

Transport has long been an underlying theme of research, including time-use, kilometres travelled, and electric vehicles (EVs).

Longden, T., Gatarin, G., Hellany, A., Leditschke, A., Kuch, D., Morrison, G., & Morrison, N. (2024). Driving change by supporting electric vehicle ready apartments. (APPI Policy Insights Paper). Australian Public Policy Institute.

Moutou, C., Longden, T., Stopher, P. and Liu, W. (2015) The challenges and opportunities of in-depth analysis of multi-day and multi-year data, Journal of Transport Economics and Policy, Vol. 49, No. 4: 579-602.

Carrara, S. & Longden, T. (2017) Freight futures: the potential impact of road freight on climate policy, Transportation Research Part D: Transport and Environment, Vol. 55: 359-372.

Longden, T. (2014) Travel intensity and climate policy: the influence of different mobility futures on the diffusion of battery integrated vehicles, Energy Policy, Vol. 72: 219-234.

Bosetti, V. and Longden, T. (2013) Light duty vehicle transportation and global climate policy: the importance of electric drive vehicles, Energy Policy, Vol. 58, July: 209-219.

Pietzcker, R., Longden, T., Chen, W., Fu, S., Kriegler, E., Kyle, P. and Luderer, G. (2014) Long-term transport energy demand and climate policy: Alternative visions on transport decarbonization in energy-economy models, Energy, Vol. 64, 1, January: 95-108.

Longden, T. (2012) Deviations in Kilometres Travelled: The Impact of Different Mobility Futures on Energy Use and Climate Policy (October 19, 2012). FEEM Working Paper No. 71., Available at SSRN: https://ssrn.com/abstract=2164217 or http://dx.doi.org/10.2139/ssrn.2164217