Research

Peer-reviewed publications:

Perdiguero, J. & Sanz, A. (2025). CO2 emissions market and renewable energy, are they linked? The case of the EU ETS, Energy Economics, Volume 148, August 2025, 108648 (Impact factor (2024): 14.2, 1/617 Economics)

ABSTRACT: Climate change is one of the main challenges facing humanity. Economic activity is generating temperature increases that can have serious economic and social effects. Various international agreements try to reduce emissions levels. The countries of the European Union adopted the emissions market system to try to modify the energy structure of their economies and thus reduce their emissions levels. This paper analyzes how the European Union Emissions Trading System (EU ETS) has been able to favour the introduction of renewable energies over fossil energies. Applying the Callaway-Sant'Anna difference-in-difference methodology, we observe how the introduction of this system within the European Union has had a positive and significant impact on the use of renewable energies. The EU ETS market has increased the use of renewables (up to 21 %) and decreased the use of fossil fuels (up to 18.4 %). This result shows that EU ETS is not only effective in reducing emissions but also in increasing the use of renewable energy. This positive effect is especially significant in the last phase when the price of emissions increases significantly. Continuing to promote this program in the future would help to increase the penetration of renewable energy in European economies.

Sanz, A. & Perdiguero, J. (2024). Does urban bus route assignment improve air quality?, Transportation Research Part D: Transport and Environment, 129C 104146 (Impact factor: 7.7, 5/61, Q1 Transportation ; 18/191, Q1 Environmental Studies)

ABSTRACT: Worldwide, one of the most important causes of mortality is air pollution. To solve this problem, governments have implemented policies to reduce on-road and industrial emissions. In this regard, the Barcelona city council and Transports Metropolitans de Barcelona (TMB) started implementing the Nova Xarxa de Bus (NXB) to redefine the bus network following the criteria of connectivity, efficiency, and rationality. This policy was implemented in seven phases from 2012 to 2018. In this context, this paper analyses the impact of this policy on Barcelona’s air quality using a dataset from 2008 to 2016. Using a difference-in-difference approach, we show that implementing these new routes increased air quality in Barcelona. Additionally, we show that pollution decreased in each phase analysed, especially in the air quality stations near the main roads. From our results, we can infer that an optimal bus route design can improve air quality in urban areas.

González, L., Perdiguero, J., & Sanz, A. (2021). Impact of public transport strikes on traffic and pollution in the city of Barcelona, Transportation Research Part D: Transport and Environment, 98C 102952 (Impact factor: 7.041, 6/37, Q1 Transportation ; 18/127, Q1 Environmental Studies)

ABSTRACT: Many Spanish cities’ air contains excessive levels of pollutants caused by traffic. These pollutants are associated with high concentrations of vehicles in urban and surrounding areas, such as Madrid and Barcelona. According to the World Health Organization (WHO), 96.8% of Spain's population breathe polluted air. This paper provides empirical evidence on the effect of public transport strikes on Barcelona’s air quality through an econometric analysis. The period analyzed included 147 days of some kind of public transport strike: bus (57), metro (21), trains (71), and tram (4); and also four general strikes. The estimates show that public transport strikes increases the concentration level of SO2, CO, PM10, and NOX throughout the city, especially in the case of metro and RENFE trains. These results also allow us to understand how commuters substitute transport modes and to propose specific policies to increase public transport use.

Perdiguero, J., & Sanz, A. (2020). Cruise activity and Pollution: The case of Barcelona. Transportation Research Part D: Transport and Environment, 78C 102181. (Impact factor: 5.495, 6/37, Q1 Transportation ; 21/125, Q1 Environmental Studies)

ABSTRACT: One of the main causes of mortality worldwide is air pollution. To tackle this problem, local, regional and national governments have implemented policies to reduce emissions from industrial and on-road sources. However, when these policies are being designed, shipping emissions are often overlooked. There has been a drastic increase in the demand for cruises and its economic relevance is also growing in port-cities. Barcelona is Europe’s leading cruise port, and it is located near the centre of the city. In this context, this paper analyses the impact of cruise ships in the air quality of the entire city of Barcelona using a dataset with information about pollutants and the number of cruises arriving to the port. We show that there is a direct impact between cruises staying at the port and city pollution. Additionally, the size and age of the cruise also affect air quality. The larger (or newer) the cruise is, the higher the emission generated. Moreover, our simulations show that the whole city is affected by these emissions.

Gomez, M., Perdiguero, J., & Sanz, A. (2019). Socioeconomic factors affecting water access in rural areas of low and middle income countries. Water (Switzerland), 11(2). (Impact factor: 2.554, 31/94, Q2 Water Resources)

ABSTRACT: Worldwide, 844 million people still lack access to basic drinking water, especially in the rural areas of low and middle income countries. However, considerable progress has been made in recent years due to work on the Millennium Development Goals and Sustainable Development Goals. Nevertheless, countries’ national characteristics have often impacted on this progress. This paper analyzes whether specific socioeconomic factors affect access to improved water sources in the rural areas of developing countries. In particular, we analyze access to ‘total improved’, piped on premises, as well as other improved sources of access in rural areas for low income, low-middle income, and high-middle income countries. Our results suggest that gross national income (GNI); female primary completion rate; agriculture; growth of rural population; and governance indicators, such as political stability, control of corruption, or regulatory quality are variables related to water access, although specific associations depend on the source of water and income group examined. Understanding these interrelations could be of great importance for decision makers in the water sector as well as for future research on this topic.

You can download the paper, HERE

Calzada, J., & Sanz, A. (2018). Universal access to clean cookstoves: Evaluation of a public program in Peru. Energy Policy, 118, 559–572. (Impact factor: 4.880, 13/363, Q1 Economics ; 14/116 Q1 Environmental Studies; 22/103, Q1 Energy & Fuels; 35/251, Q1 Environmental Sciences)

ABSTRACT: The use of biofuels for heating and cooking is the main cause of indoor air pollution in developing countries, and one of the main causes of acute respiratory infections. To tackle this problem, in 2012, the Peruvian Government created the FISE program, which subsidizes the replacement of traditional stoves with gas cookstoves. This paper describes the challenges faced during the implementation of the FISE, such as the selection of beneficiaries and the creation of a national network of suppliers for the delivery of liquefied petroleum gas (LPG) cylinders. Using a dataset with information collected from five districts in the department of Ayacucho in 2015, we apply propensity score matching at the household level to evaluate the effects of the program. We show that the FISE favored the adoption of the LPG cookstoves, but that many households still combine their use with traditional cookstoves. We find no evidence that the use of LPG stoves has reduced respiratory problems in the beneficiary households; however, the program has been found to increase the use of LPG stoves for boiling water, which may reduce the exposition of child in beneficiary households to water-related diseases.

Calzada, J., Iranzo, S., & Sanz, A. (2017). Community-Managed Water Services: The Case of Peru. Journal of Environment and Development, 26(4), 400–428. (Impact factor: 2.313, 17/57, Q2 Planning and Development; 42/109, Q2 Environmental Studies)

ABSTRACT: Due to lack of economic resources and the geographical dispersion of the population, state and private for-profit water provision is not feasible in many remote rural areas of developing countries. In such instances, community-managed water systems emerge as an alternative mechanism to provide safe water. Despite their importance, little is known about this type of organizations. This article examines the Juntas Administradoras de Servicios de Saneamiento (JASS), communal organizations that provide water services to more than 3 million people in rural and peri-urban areas of Peru. We focus on two important and related dimensions of the JASS. First, we empirically identify the factors associated to their existence (economic resources of the municipalities, tradition of communal work, and ethnic homogeneity). And second, we examine their organization and how they manage the water systems, which is importantly affected by the socioeconomic characteristics of the communities. Using the Peruvian JASS as a showcase, this article sheds then some light on the potential viability of this type of organizations. We conclude that the JASS might be an important and effective alternative to organize the provision of water services in rural and isolated areas. However, the consolidation of these institutions requires adequate supervision to ensure that water systems are correctly designed and managed and that internal governance problems do not compromise their sustainability.