The economic valuation, pricing and promotion of recycled water

This thesis topic is the evaluation of recycled water in Crete, Greece. Recycled water is a derivative of fresh water and as such it can be regarded as a good of a similar nature to fresh water (at least for some of its uses such as irrigation). The departure point for this research was given by specific articles and principles of the 60/2000 Water Framework Directive. According to them, recycled water evaluation can be viewed as a corollary of this directive. Since Crete is a European region with intense water shortage problems, this was a good opportunity to apply the suggestions of the directive: solve the problem of water shortage internally (i. e. in Crete, with the island's own means and plans, since Crete can be regarded as a single river basin district), make the most of marginal waters while at the same time enhancing the environment. The evaluation of recycled water has been implemented through the involvement of two distinctive groups of people: farmers and consumers. Therefore, on the one hand, the research asks farmers whether they would be willing to use recycled water of certain qualities for the irrigation of olive trees and tomatoes and on the other hand, the research asks consumers whether they would be willing to use and pay for food products irrigated with recycled water. Results show there is social acquiescence on recycled water usage. This is confirmed by the correspondence of willingness to use recycled water between farmers and consumers. Conclusions from the willingness to use and willingness to pay models provide useful pricing and marketing signals for recycled water. Besides the evaluation of recycled water, another part of the research dealt with the role water plays in the production of olive oil and the confirmation of irrigation water shortages

Quantitative studies and Hydrodynamical limits for interacting particle systems

The main results of my work contribute to the mathematical study of microscopic non-equilibrium systems that were first introduced in order to derive macroscopic physical laws such as Fourier's law. In particular the main objective is to determine the scaling of the spectral gap, i.e. the relaxation rate, in terms of the number of the particles for a paradigmatic model describing heat transport, the chain of oscillators. The mathematical study of this model started at the end of $90$s and it is challenging due to the degeneracy of the dynamics as the noise is not assumed to act to all the degrees of freedom, leading to lack of ellipticity and coercivity. We give bounds on the spectral gap for weak nonlinearities of the chain, i.e. perturbations around linear homogeneous chains and also a complete answer for the linear, homogeneous and disordered, chain of oscillators as well as $d$-dimensional grids of oscillators. The methods range from hypocoercivity inspired techniques, in the sense of Villani, to spectral analysis of discrete Schrödinger operators. Moreover we study heat conduction in gases addressing, with both analytic and probabilistic techniques, the question of the existence, and properties, of a non-equilibrium steady state for the nonlinear BGK model, introduced by Bhatnagar, Gross and Krook, with diffusive boundary conditions. The case that we address concerns large boundary temperatures away from the equilibrium case. Furthermore, besides non-equilibrium phenomena in many particle systems, this thesis deals with the question of deriving nonlinear diffusion equations from microscopic stochastic processes. We present a new, quantitative, unified method to show that the particle densities of one-dimensional processes on a periodic lattice, including the zero-range and simple exclusion jump processes as well as diffusion processes of Ginzburg-Landau type, converge to the solution of a nonlinear diffusion equation with an explicit, uniform in time, convergence rate. We discuss how we can extend the result to all the dimensions. Finally a study of the scaling of the spectral gap for all the mean field $\mathcal{O}(n)$ models of Ginzburg-Landau type using semiclassical tools, is included in this thesis. This concerns the spectral gap as a function of the number of particles, spins, for the dynamics below and at the critical temperature, with and without an external magnetic field.EPSR

L2L^2-stability near equilibrium for the 44 waves kinetic equation

We consider the four waves spatial homogeneous kinetic equation arising in wave turbulence theory. We study the long-time behaviour and existence of solutions around the Rayleigh-Jeans equilibrium solutions. For cut-off'd frequencies, we show that for dispersion relations weakly perturbed around the quadratic case, the linearized operator around the Rayleigh-Jeans equilibria is coercive. We then pass to the fully nonlinear operator, showing an $L^2$ - stability for initial data close to Rayleigh-Jeans.Comment: 23 pages, 1 figur

Properties of Non-Equilibrium Steady States for the non-linear BGK equation on the torus

We study the non-linear BGK model in 1d coupled to a spatially varying thermostat. We show existence, local uniqueness and linear stability of a steady state when the linear coupling term is large compared to the non-linear self interaction term. This model possesses a non-explicit spatially dependent non-equilibrium steady state. We are able to successfully use hypocoercivity theory in this case to prove that the linearised operator around this steady state posesses a spectral gap.Comment: 41 page

Spectral analysis and phase transitions for long-range interactions in harmonic chains of oscillators

We consider chains of $N$ harmonic oscillators in two dimensions coupled to two Langevin heat reservoirs at different temperatures - a classical model for heat conduction introduced by Lebowitz, Lieb, and Rieder \cite{RLL67}. We extend our previous results \cite{BM20} significantly by providing a full spectral description of the full Fokker-Planck operator allowing also for the presence of a constant external magnetic field for charged oscillators. We then study oscillator chains with additional next-to-nearest-neighbor interactions and find that the spectral gap undergoes a phase transition if the next-to-nearest-neighbour interactions are sufficiently strong and may even cease to exist for oscillator chains of finite length

An Antidote to the Resource Curse: The Blessing of Renewable Energy

This paper empirically examines the validity of the resource curse in Europe and it is the first time renewable energy is inserted in this research context. The study uses panel data with a variety of explanatory variable proxies for investment, openness, rule of law, resource endowments and human capital. It employs a single equation fixed effects model with heteroskedasticity robust covariance and a simultaneous two equation model where renewable energy enters the structural equation as an endogenous variable. The resource curse is confirmed only for crude oil and resource productivity in the single equation model while renewable energy has a positive relationship to growth. In the simultaneous two equation model, countries with high oil production and emissions also have a higher production of renewable energies.  Keywords: Natural resource curse; economic growth, renewable energy; Europe; fixed effects model  JEL Classifications; O52; P28; P48; P52; Q2

Greece & Turkey; Assessment and Comparison of Their Renewable Energy Performance

This paper is a comparative review of the renewable energy performance of Turkey and Greece. Both neighboring countries sharing the same energy hub with a large potential for renewable energy production. Albeit having strikingly similar energy objectives and hindrances, they are currently challenged by different contexts. Turkey, although not a European Union member, it spends efforts to tacitly comply with European Union legislation and sets ambitious renewable energy targets. Greece on the other hand is afflicted by an economic crisis that threatens to retard its renewable energy developments unless Greece uses renewable energy sources as a means to escape the crisis. This paper is useful for potential renewable energy investors in the area of Greece and Turkey. Keywords: Greece; renewable energy sources; Turkey JEL Classifications: O13; O57; Q2