Options
Doherty, Ronan
Preferred name
Doherty, Ronan
Official Name
Doherty, Ronan
Research Output
Now showing 1 - 5 of 5
- PublicationBurning peat in Ireland : an electricity market dispatch perspective(Elsevier, 2009-08)
; ; ; ; This paper examines peat power production in Ireland under the three pillars of energy policy—security, competitiveness and environment. Peat contributes to energy security—as an indigenous fuel, it reduces dependency on imports. During a period of low capacity margins, the operation of the peat plants is useful from a system security perspective. Peat generation is being financially supported by consumers through an electricity levy. The fuel also has high carbon intensity. It is not politically viable to consider peat on equal economic criteria to other plant types because of history and location. This paper reviews electricity generation through combustion of peat in Ireland, and quantifies the costs of supporting peat utilising economic dispatch tools, finding the subsidy is not insignificant from a cost or carbon perspective. It shows that while peat is beneficial for one pillar of energy policy (security), the current usage of peat is not optimal from a competitiveness or environmental perspective. By switching from the current ‘must-run’ mode of operation for peat to the ‘dispatched’ mode used for the other generation, significant societal savings (in the range €21m per annum) can be achieved, as well as reducing system emissions by approximately 5% per year.6126Scopus© Citations 28 - PublicationThe efficiency of Ireland's Renewable Energy Feed-In Tariff (REFIT) for wind generationIreland's Renewable Energy Feed-In Tariff (REFIT) for wind generation has some unusual features making it different from other REFIT schemes around the world. By utilising an annual floor price element the scheme presents an option value to the contract holder, which to date has gone unnoticed or unvalued in the market. By employing an option pricing framework, this paper has quantified for the first time in the public domain the expected costs and value of the Irish REFIT support scheme for wind generation. While the cost of the REFIT scheme to the electricity consumer appears to be lower than the cost of schemes in other countries, significant inefficiencies exist as a result of the structure of the scheme. The Irish REFIT scheme is contrasted with a single Fixed Price support scheme and the analysis suggests that the Fixed Price scheme can provide a similar or greater incentive to the wind sector at half the cost to the end electricity consumer, and may also prove more compatible with consumers desire to reduce inter-year electricity portfolio cost volatility.
3259Scopus© Citations 23 - PublicationQuantifying reserve demands due to increasing wind power penetrationWith wind power penetration increasing in many systems worldwide, operational issues are beginning to emerge due to the uncertain nature of wind power. One of these issues is the provision of reserve for system security. To analyse this, one must consider generator outage rates, system load forecast errors and wind power forecast errors in such a way as to directly relate the system reserve level to the security of the system. In this paper a new methodology is proposed for the analysis and provision of system reserve levels. The methodology considers the provision of both reserve (on-line) and replacement reserve (offline). The proposed methodology is then applied to the IEEE reliability test system incorporating other influencing factors like wind farm size and numbers and forecast periods. Results illustrate the impact increasing wind power penetration has on reserve.
1130Scopus© Citations 71 - PublicationGeneration portfolio analysis for a carbon constrained and uncertain futureMany modern electricity systems are faced with the challenge of reducing green house gas emissions and dealing with increasing and more volatile fuel prices. Adequately dealing with these issues requires the evolution of suitable generation portfolios. However, doubts remain if the liberalized marketplace will deliver such portfolios. Analysis is undertaken to try and determine how the generation portfolio on the all-Ireland system may evolve by 2020. Resulting portfolios are examined with respect to the impact of carbon costs on the development of the portfolio and in particular wind energy. An assessment is made of the exposure of the portfolios to fuel price volatility and how portfolios may wish to diversify to avoid this. The analysis endeavours to gain insight into the future generation portfolios with the aim of informing how policy instruments may be tailored to address these issues.
622Scopus© Citations 16 - PublicationAn assessment of the impact of wind generation on system frequency control(IEEE, 2010-02)
; ; ; ; ; Rising wind generation penetrations and the distinctive inertial characteristics of associated turbine technology will impact system frequency control. While wind production will displace conventional synchronous plant, empirical study data presented also suggest that the relationship between the total stored turbine kinetic energy and the total system power production for wind is a variable that exhibits significant nonlinearity. Changing trends in system frequency behavior of a power system following the loss of the largest generator are studied in detail here, using simplified frequency control models and extensive simulations of wind penetration scenarios over an extended multiyear timeframe. The system frequency response is characterized by the rate of change of frequency and the frequency nadir. Results show that increasing levels of doubly fed induction generators and high-voltage dc interconnection alter the frequency behavior significantly, and that system operators may have to be proactive in developing solutions to meet these challenges.3821Scopus© Citations 262