Energy production is associated with environmental impairment. Most anxious is the greenhouse gas emissions, which also arise from transportation. If battery electric vehicles should be able to alleviate the problem, they must be charged with environmentally friendly produced electricity. This paper investigates a possible relationship between battery electric vehicles and solar photovoltaic panels in household survey data from ENABLE.EU performed in ten European countries autumn 2017 – spring 2018. Estimated with a logit binary choice model, it is found that the probability that a household owns a battery electric vehicle increases if the household owns solar photovoltaic panels. Furthermore, this increase in probability is higher within countries with a higher market diffusion of battery electric vehicle and solar photovoltaic panels (France and the UK). This suggests that policy encouraging home charging of battery electric vehicles from solar photovoltaic panels that includes an energy storage facility could speed up the transition of the vehicle fleet.

The European Union has adopted a range of policies aiming at reducing greenhouse gas emissions from road transport, including setting binding targets for tailpipe CO2 emissions for new light-duty fleets. The legislative framework for implementing such targets allows taking into account the CO2 savings from innovative technologies that cannot be adequately quantified by the standard test cycle CO2 measurement. This paper presents a methodology to define the average productivity of vehicle-mounted photovoltaic roofs and to quantify the resulting CO2 benefits for conventional combustion engine-powered passenger cars in the European Union. The method relies on the analysis of a large dataset of vehicles activity data, i.e. urban driving patterns acquired with GPS systems, combined with an assessment of the shading effect from physical obstacles and indoor parking. The results show that on average the vehicle photovoltaic roof receives 58% of the available solar radiation in real-world conditions, making it possible to reduce CO2 emissions from passenger cars in a range from 1% to 3%, assuming a storage capacity of 20% of the 12 V battery dedicated to solar energy. This methodology can be applied to other vehicles types, such as light and heavy-duty, as well as to different powertrain configurations, such as hybrid and full electric.

As energy prices keep increasing, energy efficiency measures have come to the spotlight, especially in the residential sector. In this context, energy audits appear as powerful tools in order to assess the energy use and cost of energy of a dwelling, and identify possible energy saving measures that increase the energy efficiency and reduce costs. This work performs an energy audit of a single-family house (SFH) built in the 1970s which uses district heating, located in Gävle, Sweden. An empirical and quantitavive approach is followed, where energy data from the bills of 2022 together with on-site ventilation measurements is combined as a way to determine the energy inflows and outflows of the dwelling. Results concluded that the ventilation needs to be improved as a way to meet the Swedish building regulations. In addition, the energetic situation could be improved by means of the installation of solar photovoltaic (PV) modules to cover part of the electricity demand and solar thermal collectors to cover part of the domestic hot water demand. These measures would decrease the costs of the energy bills 4689 SEK/year at the time they would provide a source of renewable energy. The replacement of windows was also studied, concluding the payoff time to be excessively long to be accepted.