Asymptotic freedom from induced gravity cosmology

We give conditions to obtain cosmological asymptotic freedom in scalar-tensor theories of gravity. We show that this feature can be achieved in FRW flat spacetimes since we obtain singularity free solutions where the effective gravitational constant $G_{eff}\rightarrow 0$ for $t\rightarrow -\infty$ and, for some of them, $G_{eff}\rightarrow G_{N}$ for $t\rightarrow\infty$, where $G_{N}$ is the Newton constant.Comment: 10 pages, Late

Understanding the scaling-up of community energy niches through Strategic Niche Management Theory: insights from Finland

The growing phenomenon of civil society involvement in renewable energy generation has attracted researchers’ interest. However, rather little is known of how a diverse and relatively small sector such as community energy could scale up and promote a change in energy production. We examine this issue through the lens of Strategic Niche Management (SNM) and conceptualize community energy as a socio-technical niche that holds the potential to promote a transition to renewable energy. Drawing on interview data with members of community energy projects and experts in Finland, we identify different types of community energy projects and the factors that may prevent them from scaling up. The study contributes a typology of community energy projects by showing which initiatives could be more inclined to be part of a strategy aiming at scaling up the sector. It also shows the tensions of SNM in the context of non-market-driven innovation, highlighting how exogenous factors such as cultural aspects, the specific context in which community energy develops and the characteristics of community groups are also relevant in the scaling-up process

Growth and water relations of sun-cured tobacco irrigated with saline water

Abstract We have investigated the effects of saline irrigation on growth and water relations of two sun-cured tobacco genotypes, Xp102 and Px107, which belong to the Xanthia and Perustitza tobacco ecotypes, respectively. We compared three commercial sea salt concentrations of the irrigation water (0.25%, 0.5%, and 1% w/v) plus a non-salinized control, corresponding to an electrical conductivity (ECw) of 4.4, 8.5, 15.7, 0.5 dS m-1 and osmotic potentials of -0.22, -0.35, -0.73, -0.02 MPa, respectively. The ECsoil increased with the salinity of the irrigation water. At high salinity (1%), the soil where Px107 plants were grown showed a significantly higher salinity compared to the soil of Xp102. For both genotypes, the soil water content increased at increasing salinity and during the growth season. Increasing salinity progressively reduced the leaf turgor pressure and enhanced the cellular osmotic adjustment. The latter resulted to be more pronounced in Px107 compared to Xp102 (0.36 vs. 0.20 MPa). At higher salinity (0.5% and 1%), both genotypes showed reduced leaf surface area, dry matter accumulation, water use, net assimilation rate (NAR) and crop growth rate (CGR). Px107 roots were more sensitive than shoot to salinity (3% reduction per dS m-1) and compared to Xp102 roots, which showed a reduced development only at 1% salinity. Assessment of plant salt tolerance according to the Maas and Hoffman model revealed a slope of 1-2% for both genotypes, indicating that these tobaccos are relatively more salt tolerant compared to other species

Towards low-carbon district heating : Investigating the socio-technical challenges of the urban energy transition

Publisher Copyright: © 2021 The AuthorsDistrict heating is a major energy infrastructure in many urban settlements in the world, contributing significantly to greenhouse gas emissions. Decarbonising district heating is an important step towards the realisation of a carbon-neutral society that entails considerable socio-technical change. Building on sustainability transitions literature that has dealt with socio-technical reconfiguration, this paper investigates the barriers to the implementation of a low-carbon district heating system that is based on biomass incineration minimisation and the total phasing out of fossil fuels. Empirically, the study relies on an extensive stakeholder analysis that involved 44 organisations representing technology providers, energy companies, industry organisations, policymakers, local authorities and researchers. The results show that while several stakeholder groups could converge on key issues such as the need to support certain technological niches and the danger of a biomass lock-in, divergences regarding barriers to be removed existed between policymakers, new entrant firms, and building owners. Cities were considered important actors for the implementation of the proposed low-carbon district heating concept. However, they should encourage building owners' participation in demand response schemes, decentralized renewable energy production, and the re-design of local electricity networks to support district heating electrification.Peer reviewe

Would turkeys vote for Christmas? New entrant strategies and coopetitive tensions in the emerging demand response industry

To enter a market and scale up, entrant firms often need to cooperate with their incumbent competitors, so they are in coopetition with them. Our goal is to increase the understanding of the antecedents of coopetition and the ways in which new entrant firms navigate coopetitive tensions with incumbents. Moreover, we are interested in the impacts that coopetition has on the value creation and value appropriation of new entrant firms. So far, most literature on cooperation and coopetition in energy markets has provided the perspective of the incumbents. To study the issues empirically, we interviewed 15 demand response (DR) entrants. These firms operate in Finnish energy markets, providing automated DR services, in which Finland is a forerunner country. According to our results, collaboration between new entrant DR firms and energy incumbents was needed in order to establish the new markets. In addition, cooperation with incumbents was beneficial to DR entrants since they were able to gain new customers and increase the efficiency of their resource use due to, for example, common technological development activities. We found that the structure of energy markets was an important factor in shaping the market entry of DR entrants. According to our results, new entrants can enter electricity markets without much cooperation with the incumbents, but cooperation is necessary in natural monopoly district heating markets. As new EU regulations will enhance automated DR services, the results of this study have relevance in other EU Member States where automated DR markets have not yet been established.Peer reviewe

On-going and future research at the Sulcis site in Sardinia, Italy. Characterization and experimentation at a possible future CCS pilot

National Italian funding has recently been allocated for the construction of a 350 MWe coal-fired power plant / CCS demonstration plant in the Sulcis area of SW Sardinia, Italy. In addition, the recently approved EC-funded ENOS project (ENabling Onshore CO2 Storage in Europe) will use the Sulcis site as one of its main field research laboratories. Site characterization is already ongoing, and work has begun to design gas injection experiments at 100-200 m depth in a fault. This article gives an overview of results to date and plans for the future from the Sapienza University of Rome research group

Preliminary results of geological characterization and geochemical monitoring of Sulcis Basin (Sardinia), as a potential CCS site

The Sulcis Basin is an area situated in SW Sardinia (Italy) and is a potential site for the development of CCS in Italy. This paper illustrates the preliminary results of geological characterization of fractured carbonate reservoir (Miliolitico Fm.) and the sealing sequence, composed by clay, marl and volcanic rocks, with a total thickness of more than 900 m. To characterize the reservoircaprock system an extensive structural-geological survey at the outcrop was conducted. It was also performed a study of the geochemical monitoring, to define the baseline conditions, measuring CO2 concentrations and flux in the study site