11 research outputs found
Electric vehicles as a mean to reduce, energy, emissions and electricity costs
Electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs), which obtain their fuel from the grid by charging a battery, are set to be introduced into the mass market and expected to contribute to oil consumption reduction. This research is concerned with studying the potential impacts on the electric utilities of large-scale adoption of plug-in electric vehicles from the perspective of electricity demand, fossil fuels use, CO2 emissions and energy costs. Simulations were applied to the Portuguese case study in order to analyze what would be the optimal recharge profile and EV penetration in an energy-oriented, an emissions-oriented and a cost-oriented objective. The objectives considered were: The leveling of load profiles, minimization of daily emissions and minimization of daily wholesale costs. Almost all solutions point to an off-peak recharge and a 50% reduction in daily wholesale costs can be verified from a peak recharge scenario to an off-peak recharge for a 2 million EVs in 2020. A 15% improvement in the daily total wholesale costs can be verified in the costs minimization objective when compared with the off-peak scenario result
Metaheuristic approach to the Holt-Winters optimal short term load forecast
Electricity short-term load forecast is very
important for the operation of power systems. In this work a
classical exponential smoothing model, the Holt-Winters with
double seasonality was used to test for accurate predictions
applied to the Portuguese demand time series.
Some metaheuristic algorithms for the optimal selection of the
smoothing parameters of the Holt-Winters forecast function were
used and the results after testing in the time series showed little
differences among methods, so the use of the simple local search
algorithms is recommended as they are easier to implement
Technical and economic assessment of energy from Tidal Currents
The present work aims to study the feasibility of
deploying a farm of sea current turbines for electricity generation
in Portugal. An approach to the tides, which are they, how they
are formed, its prediction, is held. It is also conducted a study
about the energy of sea currents and it is presented some
technology about ocean currents too. A model of tidal height and
velocity of the currents it is also developed. The energy produced
by a hypothetical park, built in Sines (Portugal), is calculated and
afterwards, an economical assessment is performed for two
possible scenarios and a sensitivity analysis of NVP (Net Present
Value) and LCOE (Levelized Cost of Energy) is figured. The
conclusions about the feasibility of the projects are also
presented. Despite being desired due to its predictability, this
energy source is not yet economically viable as it is in an initial
state of development. To push investment in this technology a
feed-in tariff of, at least €200/MWh, should be considered
Renewable energy in Islands: an integrated proposal for electricity generation and transports
The purpose of this article is to analyse and
evaluate the economical, energetic and environmental impacts of
the increasing penetration of renewable energies and electrical
vehicles in isolated systems, such as Terceira Island in Azores
and Madeira Island.
Given the fact that the islands are extremely dependent on the
importation of fossil fuels - not only for the production of energy,
but also for the transportation’s sector – it’s intended to analyse
how it is possible to reduce that dependency and determine the
resultant reduction of pollutant gas emissions.
Different settings have been analysed - with and without the
penetration of EVs. The Terceira Island is an interesting case
study, where EVs charging during off-peak hours could allow an
increase in geothermal power, limited by the valley of power
demand. The percentage of renewable energy in the electric
power mix could reach the 74% in 2030 while at the same time, it
is possible to reduce the emissions of pollutant gases in 45% and
the purchase of fossil fuels in 44%. In Madeira, apart from wind,
solar and small hydro power, there are not so many endogenous
resources and the Island’s emission factor cannot be so reduced
as in Terceira. Although, it is possible to reduce fossil fuels
imports and emissions in 1.8% in 2030 when compared with a
BAU scenario with a 14% of the LD fleet composed by EVs
Optimização de uma rede de transporte de energia eléctrica
O trabalho desenvolvido nesta tese tem por objectivo a implementação de um pequeno sistema informatizado para suporte ás decisões de planeamento de pequenas redes de transporte de energia eléctrica....
Micro-generation Evaluation of the Zero Emissions Technologies in the Portuguese Market
Micro-generation is the small scale production of heat and/or electricity from a low carbon source and can be a powerful driver for carbon reduction, behavior change, security of supply and economic value. The energy conversion technologies can include photovoltaic panels, micro combined heat and power, micro wind, heat pumps, solar thermal systems, fuel cells and micro hydro schemes. In this paper, a small research of the availability of the conversion apparatus and the prices for the micro wind turbines and photovoltaic systems is made and a comparison between these two technologies is performed in terms of the availability of the resource and costs. An analysis of the new legal framework published in Portugal is done to realize if the incentives to individualspsila investment in sustainable and local energy production is worth for their point of view. An economic evaluation for these alternatives, accounting with the governmentpsilas incentives should lead, in most cases, into attractive return rates for the investment. Apart from the attractiveness of the investment there are though other aspects that should be taken into account and those are the benefits that these choices have to us all. The idea is that micro-generation will not only make a significant direct contribution to carbon reduction targets, it will also trigger a multiplier effect in behavior change by engaging hearts and minds, and providing more efficient use of energy by householders. The diversified profile of power generation by micro-generators, both in terms of location and timing, should reduce the impact of intermittency or plant failures with significant gains for security of supply
The electric vehicles as a mean to reduce Co2 emissions and energy costs in isolated regions: the São Miguel (Azores) case study
Most of small islands around the world today, are dependent on imported fossil fuels for the majority of their energy needs especially for transport activities and electricity production. The use of locally renewable energy resources and the implementation of energy efficiency measures could make a significant contribution to their economic development by reducing fossil fuel imports. An electrification of vehicles has been suggested as a way to both reduce pollutant emissions and increase security of supply of the transportation sector by reducing the dependence on oil products imports and facilitate the accommodation of renewable electricity generation, such as wind and, in the case of volcanic islands like Sao Miguel (Azores) of the geothermal energy whose penetration has been limited by the valley electricity consumption level. In this research, three scenarios of EV penetration were studied and it was verified that, for a 15% LD fleet replacement by EVs with 90% of all energy needs occurring during the night, the accommodation of 10 MW of new geothermal capacity becomes viable. Under this scenario, reductions of 8% in electricity costs, 14% in energy, 23% in fossil fuels use and CO2 emissions for the transportation and electricity production sectors could be expected
Metaheuristhic approach to the Holt-Winters optimal short term load forecast
Electricity short-term load forecast is very
important for the operation of power systems. In this work a
classical exponential smoothing model, the Holt-Winters with
double seasonality was used to test for accurate predictions
applied to the Portuguese demand time series.
Some metaheuristic algorithms for the optimal selection of the
smoothing parameters of the Holt-Winters forecast function were
used and the results after testing in the time series showed little
differences among methods, so the use of the simple local search
algorithms is recommended as they are easier to implement
Short-term Value for the Water Stored in Headsensitivity Power System Reservoirs
As it is well known, competitive electricity markets require new computing tools for generation companies to enhance the management of its resources. The economic value of the water stored in a power system reservoir is crucial information for enhancing the management of the reservoirs. This paper proposes a practical deterministic approach for computing the short-term economic value of the water stored in a power system reservoir, emphasizing the need to considerer water stored as a scarce resource with a short-term economic value. The paper addresses a problem concerning reservoirs with small storage capacities, i.e., the reservoirs considered as head-sensitivity. More precisely, the respective hydro plant is head-dependent and a pure linear approach is unable to capture such consideration. The paper presents a case study supported by the proposed practical deterministic approach and applied on a real multi-reservoir power system with three cascaded reservoirs, considering as input data forecasts for the electric energy price and for the natural inflow into the reservoirs over the schedule time horizon. The paper presents various water schedules due to different final stored water volume conditions on the reservoirs. Also, it presents the respective economic value of the water for the reservoirs at different stored water volume conditions
PV panel for self-consumption in public buildings
Nowadays, it is imperative to use renewable energy as a source for electricity generation. Energy production by self-consumption and lower costs photovoltaic (PV) panels has created a market for an increase in distributed PV generation. A self-consumption unit may waste almost all-day production if it doesn't match consumption and if there are no batteries in the system. In this case, most part of the energy generated is sold to the public grid. To avoid this situation, these panels should be installed, not in habitation houses, but in people's workplace, that is, public buildings, where photovoltaic production coincides with the load diagram peak of the building, reducing the amount of energy sold to the public grid. In addition, electricity generation decentralization avoids energy losses during transportation and distribution and reduces the number of large electrical plants, significantly contributing to the success of Paris Conference targets that are intended to slow down climate change. In summary, the main objective of this work is to study and evaluate the economic and energy impacts of photovoltaic panels installed in public buildings. Specifically, profitability study of a facility, which is very positive with an IRR of 14, % and an 8-year pay-back.info:eu-repo/semantics/publishedVersio