Urbanisation generates powerful agglomeration benefits but also severe congestion externalities that require regulation and public goods provision. In developing megacities, governments lack the fiscal and enforcement capacity to implement textbook solutions. In their absence, unregulated private provision emerges across sectors such as waste, sanitation, water, and transport, leaving externalities largely unaddressed. What can economics offer cities that cannot implement textbook policies? We study whether limited, feasible regulation can leverage informal markets to deliver public services at scale, focusing on trash collection in Accra, Ghana. Using novel data, we document an imperfect but functioning market: households pay informal tricycle collectors for door-to-door collection, yet prices remain too high for universal access, and final disposal occurs largely at illegal dumpsites. Counterfactual results show that a modest subsidy achieves roughly 80% of the efficient outcome, substantially reducing environmental damages while generating larger welfare gains at lower cost than planned infrastructure expansion.

Presentations: (2025) LSE Environment Camp, LSE IO-DEV Workshop, CURE, Guest Lecture at Kyiv School of Economics; (scheduled) STEG Annual Conference 2026

Funders & Partners: International Growth Centre (IGC), STICERD, Innovations for Poverty Action (IPA), DataPlas Ghana

Do industrial policies that promote clean energy offer a "ray of hope" increasing a country's economic growth and welfare whilst simultaneously reducing carbon emissions? We study the impact of Chinese solar subsidies whose implementation by cities coincided with a dramatic fall in global solar prices. We construct new panel data on city-level solar policies, patenting and output. Using synthetic-difference-in-differences between 2004–2020, we find that production and innovation subsidies were more effective than demand-side subsidies in generating large and persistent increases in local innovation, firm numbers, output and exports.

Presentations: (2023) NBER Summer Institute EEE, Stanford SITE; (scheduled) ASSA Annual Meeting in Philadelphia

The internal structure of cities is shaped by localised production and residential externalities. Lack of sanitation gives rise to negative externalities in the form of pollution and disease transmission. To investigate this hypothesis, we assemble an address-level data set spanning the entire construction period of the Parisian sewage network during the 19th century.

Economic growth involves the spatial and sectoral reallocation of people and firms. South Korea rose from poverty to become a leading industrialised economy in a remarkably condensed timeline. We are creating a new historical database tracking all facets of South Korea's structural transformation from the mid- to late-20th century.

Funders & Partners: Structural Transformation and Economic Growth (STEG), Economic and Social Research Council (ESRC)

Electricity is a crucial input for modern production, yet its quality across time and space varies substantially. We ask how the endogenous allocation of electricity affects firm productivity and agglomeration, combining administrative data on electricity consumption, engineering records on outages, and a detailed firm panel from a national census.

Funders & Partners: International Growth Centre (IGC)

Using geolocated information on over 400,000 water points and health surveys across Sub-Saharan Africa, we document that access to functioning water and improved sanitation increases villages' resilience to high temperatures, reducing mortality and disease incidence.

Funders & Partners: International Growth Centre (IGC)