• Energy Research
• 7. Clean energy close

Road transportation by trucks is the major part of the goods transportations system in the European Union (EU), and there is a need for increased fuel efficiency. While truck manufacturers already ...

The difference between heat losses in percentage and in absolute measures is elucidated. Good conditions for making experimental heat loss determination are outlined, i.e., to avoid varying temperatures in the ground surrounding the district heating (DH) pipes and in the pipe fluid. An overview of in-situ methods is given, and methods working on the DH pipe casing are described. Recent developments regarding quantitative thermography are also described. A comparison of the methods on an operating preinsulated transmission line is presented.

Azerbaijan has committed to cut GHG emissions by 35% by 2030 under the Paris Agreement. By applying LEAP, a well-regarded forecasting model based on inventories defined under the IPCC (Intergovernmental Panel on Climate Change), GHG emissions projections are modeled in three scenarios: a without measures (WOM) scenario or business-as-usual, which assumes no change to current behavior, a with existing measures (WEM) scenario, which takes into account currently planned measures in Azerbaijan, and an EU policy scenario, which mirrors the existing mitigation measures of the European Union. The WOM scenario of total GHG emissions from the energy sector indicates that from 2010 to 2030, total emissions will increase by 67% in Azerbaijan. In the WEM scenario, forecasted GHG emissions are only 29.7% lower than the base year and still above the nation's Paris Agreement commitment. In the EU policy scenario, projected GHG emissions are 37.2% lower than the base year. Therefore, current mitigation measures are insufficient for Azerbaijan to meet its commitments to the Paris Agreement, and stronger measures than currently planned are necessary. Because of its status as a developing nation with limited resources, Azerbaijan must have funding from developed nations promised under the Paris Agreement to transition towards a less carbon-heavy economy.

Abstract A single-phase three-wire grid-connected power converter (STGPC) with energy storage for positive grounding photovoltaic generation system (PGPGS) is proposed in this paper. The positive terminal of the solar cell array can be directly connected to the ground to avoid unexpected degradation of the special thin-film solar cell array. The proposed PGPGS consists of a solar cell array, two DC–DC power converters, a battery set, a switch set and a three-port power converter. The three-port power converter comprises a high-voltage DC port, a low-voltage DC port and an AC port. The solar cell array is connected to the high-voltage DC port through two DC–DC power converters whose positive terminal is directly connected to the ground. The battery set is connected to the low-voltage DC port, and the AC port is connected to the utility. No transformer is required in this PGPGS even when using the low-voltage battery set. A prototype is developed and tested to verify the performance of the PGPGS. The experimental results show that the proposed power converter has the expected performance.

The Intergovernmental Panel on Climate Change (IPCC) report that to limit warming to 1.5 °C, Bioenergy with Carbon Capture and Storage (BECCS) is required. Integrated assessment models (IAMS) predict that a land area between the size of Argentina and Australia is required for bioenergy crops, a 3–7 time increase in the current bioenergy planting area globally. The authors pose the question of whether vertical farming (VF) technology can enable BECCS deployment, either via land sparing or supply. VF involves indoor controlled environment cultivation, and can increase productivity per unit land area by 5–10 times. VF is predominantly being used to grow small, high value leafy greens with rapid growth cycles. Capital expenditure, operational expenditure, and sustainability are challenges in current VF industries, and will affect the ability to utilise this technology for other crops. The authors argue that, whilst challenging, VF could help reach wider climate goals. Application of VF for bioenergy crops could be a game changer in delivering BECCS technologies and may reduce the land footprint required as well as the subsequent associated negative environmental impacts. VF bioenergy could allow us to cultivate the future demand for bioenergy for BECCS on the same, or less, land area than is currently used globally.

New pressures in the electricity sector have led some analysts to reexamine the traditional utility business model and the regulatory compact that supports it. Performance-based regulation is one possible alternative to traditional regulation that starts with the outcomes that matter to customers, utilities, and other industry participants. This article describes examples of performance-oriented regulation and draws regulatory design principles from them.

Abstract This paper addresses the importance of the probabilistic analysis in determining the wave energy potential to support the design of electrical generators for wave energy conversion. The irregular activity of ocean waves induces variable frequencies and amplitudes of operation for point absorbers electrical generators, which may lead to the construction of inefficient electrical machines. Applying probabilistic models to describe the ocean wave's behavior allows the determination of the values most likely to be sampled for ocean-state parameters. Knowing these values, the most expected ocean wave potential can be determined and a proper device design can be performed. This work also refers to the importance of using the joint probability models instead of the marginal ones. Seven locations at the Portuguese coast are evaluated in order to determine their wave energy resource potential.

Spirodela oligorrhiza, a promising duckweed identified in previous studies, was examined under different cropping conditions for nutrient recovery from swine wastewater and biomass production. To prevent algae bloom during the start-up of a duckweed system, inoculating 60% of the water surface with duckweed fronds was required. In the growing season, the duckweed system was capable of removing 83.7% and 89.4% of total nitrogen (TN) and total phosphorus (TP) respectively from 6% swine lagoon water in eight weeks at a harvest frequency of twice a week. The total biomass harvested was 5.30 times that of the starting amount. In winter, nutrients could still be substantially removed in spite of the limited duckweed growth, which was probably attributed to the improved protein accumulation of duckweed plants and the nutrient uptake by the attached biofilm (algae and bacteria) on duckweed and walls of the system.

The present paper proposes a methodology for the optimal simultaneous choice of allocation and sizing of Fast Charging Stations for electric vehicles. The methodology is implemented by a Multi-Objective optimization algorithm, based on the Non-dominated Sorting Genetic Algorithm, and by using by using a probabilistic load flow. The optimised planning procedure of two coupled electrical distribution and transportation systems is applied to a case study and the results are presented to demonstrate the feasibility and consistency of the developed models used to implement the method. This approach gives the opportunity to find a proper trade-off between the conflicting interests of different stakeholders, such as the Distribution Network Operator, the Fast Charging Stations owners and the Plug-in Electric Vehicles drivers.