Emergence of District-Heating Networks; Barriers and Enablers in the Development Process

Infrastructure provision business models that promise resource efficiencies and additional benefits, such as job creation, community cohesion and crime reduction exist at sub-national scales. These local business models, however, exist only as isolated cases of good practice and their expansion and wider adoption has been limited in the context of many centralised systems that are currently the norm. In this contribution, we present a conceptual agent based model for analysing the potential for different actors to implement local infrastructure provision business models. The model is based on agents’ ability to overcome barriers that occur throughout the development (i.e. feasibility, business case, procurement, and construction), and operation and maintenance of alternative business models. This presents a novel approach insofar as previous models have concentrated on the acceptance of alternative value provision models rather than the emergence of underlying business models. We implement the model for the case study of district heating networks in the UK, which have the potential to significantly contribute to carbon emission reductions, but remain under-developed compared with other European countries

The factors determining uptake of energy crop cultivation and woodland creation in England: Insights from farmers and landowners

Perennial energy crops (PECs) and trees have key roles to play in delivering the negative emissions needed for the UK to reduce greenhouse gas emissions to net zero by 2050. Significant changes to land use are needed and the decision to make changes will lie with individual landowners. Using in-depth, semi-structured interviews, this research explores the attitudes of farmers and landowners in England to replacing traditional arable and livestock farming with growing annual or perennial energy crops or planting trees. It was concluded that considerable government policy intervention will be needed to overcome the many economic and social barriers in place including lack of markets and attractive contracts for growers, high establishment costs, loss of annual income, high prices available for cereal crops and the cultural division between farming and forestry. Although energy crops and woodland creation are generally researched and regulated separately, this research suggests that annual energy crops, PECs and woodland creation form a spectrum of land use options for a landowner, with the propensity to adopt these crops being determined predominantly by crop attributes including the risk of planting and the term of commitment

Cavity-enhanced absorption: detection of nitrogen dioxide and iodine monoxide using a violet laser diode

We present an application of cavity-enhanced absorption spectroscopy with an off-axis alignment of the cavity formed by two spherical mirrors and with time integration of the cavity-output intensity for detection of nitrogen dioxide (NO2) and iodine monoxide (IO) radicals using a violet laser diode at lambda = 404.278 nm. A noise-equivalent (1sigma = root-mean-square variation of the signal) fractional absorption for one optical pass of 4.5x10(-8) was demonstrated with a mirror reflectivity of similar to0.99925, a cavity length of 0.22 m and a lock-in-amplifier time constant of 3 s. Noise-equivalent detection sensitivities towards nitrogen dioxide of 1.8x10(10) molecule cm(-3) and towards the IO radical of 3.3x10(9) molecule cm(-3) were achieved in flow tubes with an inner diameter of 4 cm for a lock-in-amplifier time constant of 3 s. Alkyl peroxy radicals were detected using chemical titration with excess nitric oxide (RO2 + NO --> RO + NO2). Measurement of oxygen-atom concentrations was accomplished by determining the depletion of NO2 in the reaction NO2 + O --> NO + O-2. Noise-equivalent concentrations of alkyl peroxy radicals and oxygen atoms were 3x10(10) molecule cm(-3) in the discharge-flow-tube experiments