394 research outputs found
Congestion Management in European Power Networks: Criteria to Assess the Available Options
EU Member States are pursuing large scale investment in renewable generation in order to meet a 2020 target to source 20% of total energy sources by renewables. As the location for this new generation differs from the location of existing generation sources, and is often on the extremities of the electricity network, it will create new flow patterns and transmission needs. While congestion exists between European countries, increasing the penetration of variable sources of energy will change the current cross-border congestion profile. It becomes increasingly important for the power market design to foster the full use of existing transmission capacity and allow for robust operation even in the presence of system congestion. After identifying five criteria that an effective congestion management scheme for European countries will need, this paper critically assess to what extent the various approaches satisfy the requirements.Power market design, integrating renewables, congestion management
PolĂtica de estabilização de renda para a agricultura familiar: uma análise de risco.
Os produtores familiares foram prejudicados pelas polĂticas de substituição de importações e de modernização da agricultura, sofrendo com elevadas transferĂŞncias de renda para fora do setor. Uma forma de ressarci-los seria implementando uma polĂtica de estabilização de renda que asseguraria rentabilidade estável aos produtores. O objetivo deste artigo Ă© determinar os benefĂcios de uma polĂtica de estabilização de renda implementada na agricultura familiar para agricultores e consumidores de arroz, feijĂŁo, milho e mandioca, e os custos para agricultores comerciais nesses mercados. Utilizou-se o modelo de Newbery e Stiglitz, que considera a redução do risco com a polĂtica de estabilização de renda. A polĂtica implicaria aumento de receita para produtores familiares. Os benefĂcios de transferĂŞncia superariam os de eficiĂŞncia para produtores familiares e consumidores. Os benefĂcios para a agricultura familiar superariam os custos da agricultura comercial com a polĂtica nos mercados de feijĂŁo, mandioca e milho, e os benefĂcios totais superariam os custos totais nos mercados de feijĂŁo e milho, ao contrário ocorreria nos mercados de arroz e mandioca, embora neste fosse pequena a diferença. Conclui-se que a implementação da polĂtica seria viável nos mercados onde a participação da agricultura familiar fosse maior que a da comercial e naqueles importadores
Multiple openings and competitiveness of forward markets: experimental evidence
We test the competition enhancing effect of selling forward in experimental Cournot duopoly and quadropoly with multiple forward markets. We find that having two forward periods yields competitive outcomes and that the results are very close to the predicted theoretical results for both quantity setting duopolies and quadropolies. Our experiments lend strong support to the hypothesis that forward markets are competition enhancing. We then test a new market that allows for endogenously determined indefinitely many forward periods that only close when sellers coordinate on selling a zero amount in a forward market. We find that the outcomes under an endogenous close rule are also very competitive. These results hold for both duopolies and quadropolies
Welfare effects of unbundling under different regulatory regimes in natural gas markets
In this paper, we develop a theoretical model that enriches the literature on the pros and cons of ownership unbundling vis-a`-vis lighter unbundling frameworks in the natural gas markets. For each regulatory framework, we compute equilibrium outcomes when an incumbent firm and a new entrant compete a` la Cournot in the final gas market. We find that the entrant’s contracting conditions in the upstream market and the transmission tariff are key determinants of the market structure in the downstream gas market (both with ownership and with legal unbundling). We also study how the regulator must optimally set transmission tariffs in each of the two unbundling regimes. We conclude that welfare maximizing tariffs often require free access to the transmission network (in both regulatoy regimes). However, when the regulator aims at promoting the break-even of the regulated transmission system operator, the first-best tariff is unfeasible in both regimes. Hence, we study a more realistic set-up, in which the regulator’s action is constrained by the break-even of the regulated firm (the transmission system operator). In this set-up, we find that, for a given transmission tariff, final prices in the downstream market are always higher with ownership unbundling than with legal unbundling.info:eu-repo/semantics/publishedVersio
Scheduling of grid tied battery energy storage system participating in frequency response services and energy arbitrage
Battery energy storage
systems
(BESS)
are
widely used to smooth
power
fluctuations
and maintain the voltage and
frequency of the power feeder at a desired level.
T
he National Grid Electricity Transmission (NGET), the primary electricity
transmission network operator in the UK, has introduced various frequency response servic
es that are
designed
to provide a
real
-
time response to deviations in the grid frequency.
In this study
,
a
control
algorithm is
developed
which generates a
charge/discharge power output with respect to deviations in
the grid frequency and the requisite
service
specifications. Using
historical
UK electricity prices, a new
balancing
service scheduling approach
has
also been
developed to
maximize
energy
arbitrage
revenue
by layering
different types of balancing services
throughout the day
. Simulation result
s show that the
proposed algorithm delivers both dynamic and non
-
dynamic firm frequency response (FFR) and also enhanced frequency
response (EFR) to
NGET
specifications while
generating arbitrage revenue
as well as service availability payment
s
in the
balancing market. A comparative study is also presented to compare the yearly arbitrage revenue
obtained
from
the work
presented in this
paper and
a
previous
reference study
.
Finall
y, exper
imental results of
a
grid
-
tied
2MW
/1MWh
BESS
have
been used
for verification purposes
- …