China
Africa
Explore chapters and articles related to this topic
Hybrid Energy Systems for Building Industry
Published in Yatish T. Shah, Hybrid Energy Systems, 2021
New advancements make PV solar more effective than solar thermal, which uses a water-based solution that cannot handle freezing conditions without constant maintenance. While solar thermal may work better in some cases, PV solar is the superior choice for the average home. Furthermore, any excess energy goes back to the grid and may qualify for net metering, which creates additional savings for the homeowner and utility provider. Modules on PV solar panels do not include moving parts, so these panels typically last more than 30 years and require little to no maintenance. The combination of solar-geothermal allows the use of fewer solar panels. Also hybrid system allows continuous supply of power. Geothermal systems require only one unit of electricity for every five units of heat they produce, because 80% of their heat production comes from the earth through a ground loop system. Transferring that energy from the earth to the home requires a small amount of output, which the PV solar panels collect and convert on their own. All this makes hybrid system very efficient.
Efficient Use of Energy in Irrigation
Published in Guangnan Chen, Advances in Agricultural Machinery and Technologies, 2018
J. I. Córcoles, A. Martínez-Romero, R. Ballesteros, J. M. Tarjuelo, M. A. Moreno
PV systems have been successfully applied to irrigate different types of crops in different climates and cropping conditions. The most widespread type of stand-alone photovoltaic irrigation systems is one that is designed to pump water from wells to an elevated storage reservoir. Water is then distributed to the plants by gravity or with a booster station. Another problem that must be faced is that irrigation application times are relatively short, while the production of energy is distributed during sunlight hours, so there is a gap between offer and demand. One possibility to cope with this gap could be to establish a net metering billing policy. Net metering is a billing mechanism that credits solar energy system owners for the electricity they do not use and add to the grid. The system owners can consume the energy they have in their accounts whenever they need within the applicable billing period. Although some countries have issued regulations regarding net metering billing policies, in other countries, like Spain, these regulations have not been implemented yet. In these cases, a stand-alone direct pumping photovoltaic irrigation system is necessary, using several irrigation sectors by plot. The system must include variable speed pumps in order to adjust the power consumed by the irrigation system to the power produced by the PV array, obtaining variable discharge. The use of reservoirs can help to adjust the variable discharge to a direct injection to the irrigation system or to the reservoir.
Environment and Energy Sustainability
Published in Roy L. Nersesian, Energy Economics, 2016
On the surface, net metering is fair in that excess electricity from solar power installed on a residence or building is sold back to the utility at the same rate for electricity consumed by a residence or building when solar power is not sufficient to meet needs. The problem with this arrangement is that the utility loses revenue when a home or building is fitted with solar power, yet is expected to maintain the transmission and distribution system to guarantee a consumer’s access to electricity if and when needed. Utilities want a charge placed on electricity they must purchase from consumers to reflect the cost of maintaining transmission and distribution systems for the consumers’ benefit.80 Individuals selling excess electricity back to the utility are not in a strong bargaining position. But they can be by forming a yet-to-be-developed virtual power plant (VPP), an aggregation of many individuals acting collectively as a single entity by coordinating the individual solar installations as a unified and flexible resource. VPPs, as concentrated power suppliers, would be able to offer utilities greater flexibility to manage their grids for supplying dependable power at the lowest cost. VPPs would rely on computer software systems to remotely and automatically dispatch and optimize generation in a single, secure web-connected system.81
Techno-economic assessment of photovoltaic-based charging stations for electric vehicles in developing countries
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2023
Loiy Al-Ghussain, Adnan Darwish Ahmad, Ahmad M. Abubaker, Mohammad Alrbai, Osama Ayadi, Sameer Al-Dahidi, Nelson K. Akafuah
Other aspects of renewable energy generation are the net meter and zero-export systems. Net metering is a billing method that credits renewable energy owners for the surplus energy generated by adding it to the grid. Internationally, many state and national-level services have offered net metering resources to motivate the integration of grid-tied RE. The policies of net metering have been implemented in at least 66 countries at the national and sub-national levels (Rehman et al. 2020). In the United States, 48 states have implemented net metering policies in certain forms (Kumar, Malik, and Garg 2022). Net metering is also applied in South Asia. Some examples are India, Sri Lanka, Pakistan, and Maldives (Rehman et al. 2020). Depending on the country, net metering policy varies between national and sub-national levels. In India, the cap limit is 500 kW for Uttarakhand and Goa, while the cap in Sri Lanka is 10 MW. On the other hand, zero-export systems prevent any power from being exported to the grid. The extra power from, for example, the PV is limited if the load is lower than the solar energy generation at any time (Application note - SolarEdge technologies). Zero-export systems would reduce the hazard linked to fault currents, transformer/substation loading, and neutral voltage displacement (Export limitation | SMA solar).
Optimal sizing of grid-connected hybrid renewable energy systems without storage: a generalized optimization model
Published in Energy Sources, Part A: Recovery, Utilization, and Environmental Effects, 2020
Ozan Capraz, Askiner Gungor, Ozcan Mutlu, Aysun Sagbas
In this section, a case study for a grid-connected HRES-WS is designed for a demand point in Denizli, Turkey. Electricity demand is to be met by WT, PV panels and/or the grid. WT and PV panels are widely used in many fields and have advantages over other sources (Li 2019) and therefore these sources are selected for the possible electricity generation for the case study. Then, the proposed model is applied to the case study in order to show the applicability and the benefit of the model. It is considered that the net metering tariff is applied and the excess produced electricity can be sold to the grid. Historical hourly electricity consumption data of the location for the year 2018 is gathered from an energy company located in Denizli, Turkey. Daily average hourly electricity consumption of the location is given in Figure 3. The hourly peak consumption is 1.054 kWh which were occurred at 14.00 on November 29, 2018. Furthermore, historical hourly meteorological data such as wind speed (m/s) between 2013 and 2017, temperature (oC) between 2013 and 2017, solar irradiation (W/m2) between 2002 and 2006, etc. are collected from Denizli Meteorological Service. It is assumed that the meteorological data of the location is the same as the meteorological data collected from Denizli Meteorological Service. Hourly average (2013–2017) wind speed throughout a year and monthly average hourly (2002–2006) solar radiation during a day are depicted in Figures 4 and 5, respectively.
Non-utility Photovoltaic Deployment: Evaluation of U.S. State-level Policy Drivers
Published in Strategic Planning for Energy and the Environment, 2019
Net metering legislation has been adopted in 44 of the 50 states [25]. They create a repayment system for selling energy back to the grid once a solar PV system is interconnected [26,27]. Typically, such arrangements are a direct kilowatt hour (kWh)-for-kWh offset on a residential or commercial utility invoice for all energy produced, credited over a 12-month period [28]. These standards are vital for non-utility solar PV projects since they allow consumers to receive benefits for all of the electricity generated by their systems, even when the system's production exceeds the needs of the building on which it lies [29]. Such arrangements also allow solar PV system owners to use electricity from the grid at times when their systems are not producing (e.g., at night), negating the need for expensive battery storage, and potentially achieving net-zero electricity consumption during a given month or year. However, in some states, net metering laws are less supportive as they may limit system capacities, establish fees, or restrict the types of energy systems that are eligible for the program [30].