Abstract. The energy sector is undeniably undergoing a critical period, faced with multiple challenges, whether economic, political or technological. These challenges are related to the requirements set on the sector to meet a wide range of social demands associated with the three traditional dimensions of a sustainable energy system, i.e., environmental sustainability, security of energy supply and economic sustainability.

Abstract. The aim of this paper is to assess several pathways of a harmonised European policy framework for supporting renewable electricity (RES-E) in a 2030 horizon according to different criteria. The pathways combine two main dimensions: degrees of harmonisation and instruments and design elements. A quantitative model-based analysis with the Green-X model is provided. The results of the simulations show that there are small differences between the evaluated cases regarding effectiveness.

Abstract. The aim of this paper is to analyse the impact of several “international” drivers on firms developing or adopting eco-innovation (i.e., eco-innovators), with the help of a bivariate probit model with sample selection and using a database of Spanish innovators.

Abstract. This paper analyses the main determinants influencing different types of eco-innovations and eco-innovators in Spain. We differentiate between two types of eco-innovations (process vs. product and new-to-the-market (NTM) vs. new-to-the-firm (NTF)) and two different types of ecoinnovators (large vs. small and old vs. new firms). Our findings show that new firms are not more eco-innovative and that smaller firms are certainly less eco-innovative.

Abstract. The aim of this paper is to estimate fuel demand behaviour related to car use by households with different income levels in Spain using micro-level panel data in order to infer public policy implications. Our results show that the income elasticity of fuel demand is highest for the lowest income group and diminishes monotonically for the others. The price elasticity is highest in absolute value for the lowest income group, lowest for the highest income quartile and similar for the medium-low and medium-high income groups.

Abstract. The European Climate and Energy mix of targets and policies has been criticised by many economists. In particular, it is often argued that the renewable energy targets do not make economic sense, because they represent an expensive option to reduce CO2 emissions within a cap-and-trade scheme such as the European Union Emissions Trading Scheme (EU ETS).

Abstract. The aim of this paper is to make manifest the intellectual and cognitive structure of nanoscience and nanotechnology (NST) by means of visualization techniques. To this end, we used data from the Web of Science (WoS), delimiting the data to the category NST during the period of 2000–2013, retrieving a total of 198,275 documents. Through direct author citation of these works, we identified their origins and the seminal papers, and through word co-occurrence extracted from the titles and abstracts, the main lines of research were identified.

Abstract
Purpose
Research with stem cells is a biomedical venture with great scientific impact, and whose development flows over into many other areas. This article aims to present a dual analysis of Spain's scientific output in this field during the period 1997‐2007.

Design/methodology/approach
The authors used bibliometric indicators of a basic nature as well as techniques for the visualization and analysis of networks of scientific information based on a study of KeyWords Plus.

Abstract. This paper presents and applies an experimental agroforestry accounting system (AAS) to measure the commercial income and capital of hunting activities in a large territorial area.

Abstract. This paper proposes a novel approach for simulating the price of hunting self-consumption by owners in the experimental Agroforestry Accounting System (AAS).