Local Energy Sources Research Articles

A Decision Support Tool for Implementing District Heating in Existing Cities, Focusing on Using a Geothermal Source

In the context of climate change mitigation strategies in urban environments and reducing reliance on carbon-based energy sources, the Netherlands is gradually taking steps towards modification of its thermal energy system. Geothermal energy, widely used in agriculture, has recently emerged as a local, clean, and sustainable energy source able to fulfil the residential demand for space heating and has received growing attention in district energy planning. However, failed attempts in the past and the lack of experience with direct application of this technology in district heating systems has increased uncertainty with respect to the technical, spatial, and socioeconomic barriers to be overcome between supply and demand. This calls for the application of decision support tools in order to remove these barriers and facilitate more appropriate decision making towards the implementation of smart thermal energy grids in local energy communities. This research explores how the network of actors, those who see opportunities in direct use of geothermal energy in the Netherlands, can work on the transformation of the current centralised carbon-based energy systems towards local sustainable energy communities.

Biomass Extraction of Energy Transformation

The focus of this is to make available clean energy, where there is a need for electricity production or energy infrastructure. An anaerobic digester contains an oxygen free environment that allows microorganisms to break down the organic material to harvest biogas (methane). Once the biogas is formed it can be used for different applications to aid the developing world. There are already millions of biogas plants in operation throughout the world. In Germany and other industrialized countries, power generation is the main purpose of biogas plants; conversion of biogas to electricity has become a standard technology. Biomass can become a reliable and renewable local energy source to replace conventional fossil fuels in local industries and to reduce reliance on overloaded electricity grids. The concept presented is to use manure from farms to produce methane gas using anaerobic digestion.

Developmental regulation of microtubule-based trafficking and anchoring of axonal mitochondria in health and diseases.

Mitochondria are cellular power plants that supply most of the ATP required in the brain to power neuronal growth, function, and regeneration. Given their extremely polarized structures and extended long axons, neurons face an exceptional challenge to maintain energy homeostasis in distal axons, synapses, and growth cones. Anchored mitochondria serve as local energy sources; therefore, the regulation of mitochondrial trafficking and anchoring ensures that these metabolically active areas are adequately supplied with ATP. Chronic mitochondrial dysfunction is a hallmark feature of major aging-related neurodegenerative diseases, and thus, anchored mitochondria in aging neurons need to be removed when they become dysfunctional. Investigations into the regulation of microtubule (MT)-based trafficking and anchoring of axonal mitochondria under physiological and pathological circumstances represent an important emerging area. In this short review article, we provide an updated overview of recent in vitro and in vivo studies showing (1) how mitochondria are transported and positioned in axons and synapses during neuronal developmental and maturation stages, and (2) how altered mitochondrial motility and axonal energy deficits in aging nervous systems link to neurodegeneration and regeneration in a disease or injury setting. We also highlight a major role of syntaphilin as a key MT-based regulator of axonal mitochondrial trafficking and anchoring in mature neurons.

A framework for preliminary large-scale urban wind energy potential assessment: Roof-mounted wind turbines

Urban wind energy can provide a decentralized local source of energy for residential areas and reduce the cost of energy by avoiding the losses/costs of long-distance energy transmission. In this perspective, a preliminary assessment of urban wind energy is highly desired by turbine developers, investors and policy makers. However, given the large number of parameters involved, predictions of the wind energy potential in urban areas are very challenging. The present paper, therefore, intends to present a straightforward framework to provide a preliminary and large-scale assessment of the urban wind energy potential, i.e. at city or country scales, for roof-mounted turbines. The framework is based on four main steps: (i) collecting the building data, i.e. the number of potential candidate high-rise buildings and their height and rooftop surface area; (ii) obtaining the annual mean wind speed statistics at the height of these buildings and sorting the building data based on these statistics; (iii) obtaining the turbine characteristics and determining the average number of turbines per building roof; (iv) calculating the annual energy production (AEP). The application of the framework is then illustrated at the country scale for the Netherlands. In this case, the urban wind energy potential is assessed by considering the installation of 18,156 small wind turbines on the roofs of 1513 existing high-rise buildings in 12 major cities in the Netherlands, yielding an annual energy production of 150.1 GWh.

Thermodynamic performance analysis and multi-criteria optimization of a hybrid combined heat and power system coupled with geothermal energy

Hybrid fossil/renewable energy combined heat and power (CHP) systems harness local energy sources, save fossil fuels, and reduce greenhouse gas emissions. Here geothermal energy is integrated into a natural gas driven CHP system by employing both vapor-compressor and absorption cycles through a geothermal heat pump (GSHP). To increase the performance of the heat pumps, the mixed hot water from the internal combustion engine (ICE) is used to preheat the evaporator. Using a multi-criteria optimization method based on energy, economic, environmental and adjustable factors, the optimal allocation ratio of hot water from the ICE is analyzed to maximize the performance of the hybrid CHP system for a specific case building. The necessary thermodynamic models of the system components needed for the optimization are presented. The results demonstrate that the increasing allocation ratio of mixed water for the heat pumps raised the output and coefficient of performance (COP). At optimal allocation ratio maximizing the performance of the CHP system against a set of criteria, the optimum energy saving ratio (ESR), carbon dioxide emission reduction ratio (CDERR), annual cost saving reduction (ACSR), and adjustable ratio are 30.26%, 53.20%, 40.80% and 6.40%, respectively. The hybrid CHP system also shows much higher flexibility than other relevant systems.

Thermophysical properties of surficial rocks: a tool to characterize geothermal resources of remote northern regions

The energetic framework of Canadian remote communities relies on fossil fuels. This has adverse environmental and energy security issues. In order to offset diesel consumption, the search for local, sustainable and carbon-free energy sources is of utmost importance. Unfortunately, in such remote regions, subsurface data to evaluate the geothermal potential is often nonexistent. This raises a key question: how to characterize geothermal resources associated to petrothermal systems based on surface data? Answering this question is the purpose of this work highlighting how outcrops can be used as deep subsurface analogues. The variability induced by laboratory methods to characterize thermophysical properties is further evaluated in the estimation of the present-day temperature at depth. The community of Kuujjuaq, Canada, is used as an example where guidelines are defined to evaluate the steady-state geotherm. Rock samples were collected and analyzed with a guarded heat flow meter and an optical scanner to determine thermal conductivity. Radiogenic elements concentration was evaluated with gamma-ray and mass spectrometry. 2D temperature models were built taking into account the regional geology and the results obtained from the different laboratory methods. A base-case temperature of 57–88 °C at 5 km is predicted below Kuujjuaq. This range is based on different methods used to evaluate both thermal conductivity and internal heat generation. The work conducted in Kuujjuaq shows that the combination of gamma-ray spectrometry and optical scanning gives lower base-case temperature predictions when compared to mass spectrometry combined with the guarded heat flow meter. Despite the nonexistence of deep temperature measurements in northern regions, the assessment of thermophysical properties from outcrops is shown to be a useful tool for a preliminary assessment of geothermal resources in remote areas facing critical energy issues.

Challenges and opportunities of zero emission shipping in smart islands: A study of zero emission ferry lines

Abstract Various studies have shown that maritime sector needs increased use of zero emission vessels in service by 2030 in order to achieve an absolute reduction in CO2 emissions of 50% by 2050 (consistent with a 2 °C pathway). These vessels, with operational emissions containing zero or negligible greenhouse gas share, would need to represent a significant portion of newbuilds from that point onwards. The objective of this research is to show the opportunity that implementation of zero emission ferry lines offers in the framework of 100% RES smart island energy systems and demonstrate their ability to supply the fuel for zero emission ferry lines. A method is presented for modelling supply of ferry lines, which are fuelled from excess energy produced by local renewable energy sources. Case study analyses show that operation costs of hydrogen and electric ferry differ depending on the island size and route. Onshore investments are 60% lower in case of electric ferry for short lines, while for longer line onshore investments were up to 4 times higher than the ones needed for the hydrogen ferry line, which had 40% smaller onboard investment costs.

Optimization of Isolated Hybrid Microgrids with Renewable Energy Based on Different Battery Models and Technologies

Energy supply in remote areas (mainly in developing countries such as Colombia) has become a challenge. Hybrid microgrids are local and reliable sources of energy for these areas where access to the power grid is generally limited or unavailable. These systems generally include a diesel generator, solar modules, wind turbines, and storage devices such as batteries. Battery life estimation is an essential factor in the optimization of a hybrid microgrid since it determines the system’s final costs, including future battery replacements. This article presents a comparison of different technologies and battery models in a hybrid microgrid. The optimization is achieved using the iHOGA software, based on data from a real microgrid in Colombia. The simulation results allowed the comparison of prediction models for lifespan calculation for both lead–acid and lithium batteries in a hybrid microgrid, showing that the most accurate models are more realistic in predicting battery life by closely estimating real lifespans that are shorter, unlike other simplified methods that obtain much longer and unrealistic lifetimes.

Thermal desalination potential with parabolic trough collectors and geothermal energy in the Spanish southeast

Desalination industry has become essential for the survival of the population in places with shortages of fresh water. Because is a costly process, the constant search for the best local renewable energy sources is a necessity.A theoretical Multi-effect distillation plant of 9000 m3/d located in the southeast Spanish (Almería) is intended to fed thermally with solar (parabolic trough collectors) and geothermal energy.Starting from the history of solar irradiation and temperatures of the province of Almería from 1994 to 2016 provided by Solargis database, a discrimination of the profile of temperatures is obtained at the exit of the solar panels. Putting in common the profile exit temperatures and the potentiality of the geothermal resource at the depth in the area under study, a series of possible configurations are obtained.The theoretical results of the study indicate that during 76% of the annual time is achieved with both resources (solar and geothermal) at that depth of the well in that specific climatological zone (490 m, t = 41.8 °C).Since the thermal gradient in the area is 8.87 °C per 100 m depth according to the studies carried out, only geothermal energy would be necessary at deep of 790 m to obtain working temperatures of the desalination plant at 70 °C.Applying the results to the existing desalination plants of the Spanish project named Actions for the Management and Utilization of Water is obtained 6 years of amortization and 510,387,920 kg/y CO2 avoided to the atmosphere for all of these plants.

Local energy self-sufficiency for passive buildings: Case study of a typical Moroccan building

The building sector in Morocco represents about 25% of the country's total energy consumption, including 18% for the residential sector and 7% for the service sector. The integration of renewable energies in the building sector is the subject of a major trend in terms of future projects in Morocco. Today, Morocco is targeting a strategy that will allow it to achieve 50% of its electricity consumption from a renewable, new and clean local energy source. Through this current situation, this article has just made a positive contribution, by studying the impact of the passive part of a typical Moroccan R+1 building, in particular that of thermal insulation, on its energy self-sufficiency in different climates. TRNSYS simulation studio was used to design and develop a platform to calculate this objective in a global and specific way. This platform combines a whole hybrid system, based on two new and clean renewable energy sources (wind turbine and photovoltaic energy), to the building's thermal loads. The results show that the impact of thermal insulation on the building's energy self-sufficiency in all the studied climates is very significant, especially in Ifrane city (Morocco). Given that the energy self-sufficiency in this climate has been improved by 41.28% more than the baseline situation. Finally, we suggest that the Moroccan building thermal code should include the impact of the passive part of the building on its energy self-sufficiency in the form of numerical indicators, in order to encourage people to get involved in this development.

A novel approach for the study and analysis in designing system of smart grid

The designing of the system has made all possible energy resources, conversion efficiency, and also power demand, to control both environmental and economic issues. In this technology, the network will not only get going to integrated and set communicable all over the country but its demand will be tracked by the control centers in different aspect and at high time the usage of power is going to cost higher than the actual rate with intimation given to the customer through notification via SMS or email. Besides, they also assist with the utilities to comply with the countries regulatory for power supply utility grid and local renewable energy sources. From the conventional distribution system, we can see the design for the control of all the constituents as observed to be autonomous with each other. Thus, centralization in control and consolidated functionality are the main challenges discovered by the distribution system. To minimize these matters of concern, the term “distribution system and its responsibilities” came into effect by using information and communications technology (ICT) to power the resolution in circulating distribution systems.

The Penetration of Renewable and Sustainable Energy in Asia: A State-of-the-Art Review on Net-Metering

Conventional fossil-fuel energy resources are being drastically depleted; thus, the current shift towards renewable energy (RE) resources has become imperative. However, there are many impediments to the adoption of renewable power generation. These impediments can be overcome by enacting policies to encourage the acceptance of sustainable energy resources. For instance, the net-metering policy can provide the necessary incentives to promote the development of local distributed energy sources, primarily solar photovoltaic and wind generators. While there has been significant advancement and development in net-metering in Asia with the increased penetration of RE, at present there is a lack of systematic review in this area. This paper aims to present an in-depth review on net-metering advances and challenges, current RE shares, and future RE targets in the Asian region. Additionally, a case study is performed and an economic analysis of net-metering regulations in an Asian country is carried out. In this study, the monetary benefits of net-metering policies for residential consumers are proved. It is envisaged that the information gathered in this paper will be a valuable one-stop source of information for Asian researchers working on this topic.

Design, Modeling, and Simulation of Two‐Piece Trapezoidal Piezoelectric Devices for Sensing and Energy Harvesting

The objective of the research is to design a high power energy harvester device through a two‐piece trapezoidal geometry approach. The performance of the composite two‐piece trapezoidal piezoelectric PZT‐PZN polycrystalline ceramic material is simulated using COMSOL Multiphysics. Results are analysed using the series configuration of a two‐piece trapezoidal composite bimorph cantilever which vibrates at the first fundamental frequency. The two‐piece trapezoidal composite beam designs resulted in a full‐width half‐maximum electric power bandwidth of 2.5 Hz while providing an electric power density of 16.81 mW/cm3 with a resistive load of 0.08 MΩ. The authors believe that these results could help design a piezoelectric energy harvester to provide local energy source which provides high electric power output.

Renewable Energy on Tribal Lands: A Feasibility Study for a Biomass-to-Energy Plant on the Cocopah Reservation in Arizona

Native American reservations are among the most economically disadvantaged regions in the United States; lacking access to economic and educational opportunities that are exacerbated by “energy insecurity” due to insufficient connectivity to the electric grid and power outages. Local renewable energy sources such as wind, solar, and biomass offer energy alternatives but their implementation encounters barriers such as lack of financing, infrastructure, and expertise, as well as divergent attitudes among tribal leaders. Biomass, in particular, could be a source of stable base-load power that is abundant and scalable in many rural communities. This case study examines the feasibility of a biomass energy plant on the Cocopah reservation in southwestern Arizona. It considers feedstock availability, cost and energy content, technology options, nameplate capacity, discount and interest rates, construction, operation and maintenance (O&M) costs, and alternative investment options. This study finds that at current electricity prices and based on typical costs for fuel, O&M over 30 years, none of the tested scenarios is presently cost-effective on a net present value (NPV) basis when compared with an alternative investment yielding annual returns of 3% or higher. The technology most likely to be economically viable and suitable for remote, rural contexts—a combustion stoker—resulted in a levelized costs of energy (LCOE) ranging from US$0.056 to 0.147/kWh. The most favorable scenario is a combustion stoker with an estimated NPV of US$4,791,243. The NPV of the corresponding alternative investment is US$7,123,380. However, if the tribes were able to secure a zero-interest loan to finance the plant’s installation cost, the project would be on par with the alternative investment. Even if this were the case, the scenario still relies on some of the most optimistic assumptions for the biomass-to-power plant and excludes abatement costs for air emissions. The study thus concludes that at present small-scale, biomass-to-energy projects require a mix of favorable market and local conditions as well as appropriate policy support to make biomass energy projects a cost-competitive source of stable, alternative energy for remote rural tribal communities that can provide greater tribal sovereignty and economic opportunities.

Optimal system layout and locations for fully renewable high temperature co-electrolysis

High temperature co-electrolysis can be a promising technology for the transformation of energy systems as it enables sector coupling and carbon dioxide utilization. In this article, we analyze the optimal layout and operation of distributed electrolysis sites powered exclusively by local renewable energy sources and a local battery storage device for current techno-economic parameters. For this purpose an energy system model with a spatial resolution of 277 regions within Europe is set up, which facilitates the analysis of intermittent renewable electricity generation, a battery storage device and the innovative high temperature co-electrolysis. We discuss the techno-economic competitiveness and analyze potential leverage points for improvement such as an enhanced flexibility. The lowest costs are found in Lincolnshire with 0.24 €/kWh and the highest costs in Central Slovakia with 0.49 €/kWh differing by more than a factor of two. Remarkably, several locations with vastly different resources and layouts lead to a similar techno-economic performance of the investigated system. We compare the techno-economic performance of high temperature co-electrolysis with steam methane reforming as the conventional synthesis gas production route.

Mathematical modeling of the technological processes of catering products production

AbstractTechnological processes of catering products manufacture need energy optimization. This article proposes the improvement of mathematical modeling apparatus at the stage of technological processes design and reconstruction. The authors used data from large restaurant‐type catering enterprises typical for million‐plus cities, some of which prepare fast‐food dishes. The possibilities of calorie generation during photosynthesis and the generation of electricity by photocells were examined to understand the energy benefits for catering enterprises. Emphasis is placed on minimizing energy consumption for heating and cooling in food production cycles using cogeneration, regeneration, and generation from local renewable energy sources. Cooking and storage chambers can be differentiated by thermal potentials. The modeling algorithm is deepened by the introduction of links between power consumption and generation equipment. A set of organizational measures of reconstruction is proposed in the design of production systems, which allows one to save up to 33–80% of the total energy costs of a real network of catering outlets.Practical ApplicationsThe use of modern energy technologies in the production processes of public catering enterprises will reduce total costs by up to 80% and improve the overall environmental friendliness of the food industry. While planning reconstruction of basic energy equipment, buildings, and mechanisms, the following must be taken into account. These include concepts of a healthy diet, local renewable energy resources, cultivating local natural food ingredients, and utilizing heat and calorie emissions. Up to 50% of the existing equipment requires such a reconstruction in public catering in developing countries. The principles recommended by the authors for the reconstruction of the production processes of public catering enterprises require the use of advanced algorithms for the mathematical optimization of energy flows and balances.

Hire fast, fire slow: the employment benefits of energy transitions

The transition towards decarbonized and efficient energy systems has broad socio-economic implications. We estimate the potential impacts on employment from efforts in energy efficiency in industry, transport and buildings as well as substituting local renewable energy sources for fossil fuels. Both energy supply and demand are accounted for. We use a hybrid approach that combines national energy transition scenarios with input–output tables, adjusted for new energy and non-energy activities. We conclude that the transition has a net positive impact on employment as illustrated by the case of Switzerland. The local and decentralized nature of energy efficiency and renewables retains a greater share of value-added domestically than does a supply chain of fossil fuels. Moreover, we find that more jobs are created in demand-side activities, such as building renovation, than in renewable energy generation. Positive impacts on jobs from spillover effects in all non-energy activities are also found.

Cooperative energy management of a community of smart-buildings: A Blockchain approach

Demand Response (DR) is progressively moving from a centralized, unidirectional structure to a set of advanced decentralized mechanisms that better balance distributed supply and demand. This paper presents a decentralized cooperative DR framework to manage the daily energy exchanges within a community of Smart-Buildings, in the presence of local Renewable Energy Sources (RES). The proposed algorithm taps into the flexibility of the participants to let them decide of a day-ahead community power profile, and subsequently ensures the forecast tracking during the next day. In practice, the algorithm is fully decentralized by the Blockchain technology, that enables a trusted communication medium among the participants and enforces autonomous monitoring and billing via Smart-Contracts. With such an energy management framework, participating Smart-Buildings can together aim at a common objective, such as carbon-free resources usage or aggregated grid services, without depending on a centralized aggregator/utility. Simulations on realistic Swiss building models demonstrate that nearly all the renewable production resources could be harnessed locally through the presented framework, compared to selfish individual optimization. Under a quadratic cost of grid electricity, the considered community profile could dramatically be flattened, hence avoiding costly peaks at the grid interface. A scalability analysis shows that, considering the current public Ethereum Blockchain, the framework could handle a community size of up to 100 Smart-Buildings.

Enhanced and integrated geothermal systems for sustainable development of Canada’s northern communities

This paper provides an evaluation of the needs and requirement for the provision of critical energy services to communities in Canada’s northern region. Enhanced geothermal system concepts are introduced as part of a set of integrated solutions that are cost-competitive and sustainable over the long-term. The goal is to establish a low-carbon energy supply system that not only generates sufficient power and heat to satisfy basic needs but can be scaled to meet higher level requirements for economic empowerment. For remote and isolated communities, a reliable and cost-effective supply of energy is a critical factor to develop and sustain a standard of living comparable to southern regions of Canada. The high cost of energy supply, specifically diesel transport over long distances, is a severe impediment to sustainable development in the northern regions of Canada. A first-order technical and economic feasibility study of the integration of different local energy sources (both renewable and non-renewable) with geothermal energy (deep and shallow) is developed to establish a pathway for a more efficient, low-carbon, sustainable energy sources. The results of this analysis provide a strong basis for investment in modular small-scale integrated geothermal systems for seasonal heat storage and electricity services.

Comparison of two numerical approaches for natural convection in cavities with energy sources

A numerical investigation of two-dimensional natural convection in an enclosure with a local square energy source has been carried out. The presented problem has been solved by two numerical methods – first of all by the finite difference method using the non-primitive variables “stream function – vorticity” and by the lattice Boltzmann method. As a result the distributions of temperature fields and stream functions and also velocity fields have been obtained. A comparison of the obtained data and the evaluation of the effectiveness of methods for solving of this class of problems have been performed.