Transmission Impact Studies An impact study generally involves determining the incremental change in transmission reliability due to an addition or change in the power system. This type of study is usually part of a formalized procedure to approve new equipment and power plants interconnecting to the grid. For further information, select one of the links below:
What is Involved in Impact Studies?Some of the aspects of impact studies include - Defining reference condition/s prior to the addition of the new equipment. For instance, this may comprise of power flow models of the grid at summer and winter peak on the first year of operation of the proposed equipment. More extensively, this may include short circuit and stability models as well.
- Modifying the reference condition/s to add only the new equipment.
- Both the reference conditions and its incremented complements are tested for reliability performance. The more common tests are: contingency analysis, short circuit calculation, stability simulation, transfer analysis, torsional and prony analysis. Less frequently, there are power quality and switching transient analyses.
- Where reliability criteria are violated, a determination is made as to whether this is due to the new equipment. The factors include the magnitude of increase in violation, or any new violations attributable to the new equipment.
- The operation of the new equipment may be limited because of its impact. For example, a new power plant that may have a transmission congestion impact may be curtailed below maximum capability. Or, the equipment may be rejected if the impacts are severe.
- Reinforcements to the transmission grid in the form of line upgrades, new lines, additional reactive support, may help resolve the impacts of the new equipment.
The process is fairly involved and takes some time to conduct. Large-scale simulation models are needed to quantify impacts. Of Interest to Project DevelopersAlso, project developers may be interested in pre-impact assessment studies such as: - Fatal Flaw studies - assess the transmission requirements for a new power project using a quick but accurate analysis. Identify potential transmission fatal flaws before you get too far along on project development. Duration: 1-2 weeks.
- Site Assessment - compare the transmission impacts for several interconnection points for a proposed project. Duration: 2-4 weeks.
- Feasibility studies - assess the thermal and voltage requirements to interconnect a proposed power project using a specific model of the transmission network closest to that used in an impact study, and taking into account sensitivity to other power projects under development and contingencies that determine specific impacts. Duration: 3-6 weeks.
Pterra's ExperiencePterra has the expertise and experience to help you through the impact study process. Our team has conducted impact studies in many North American regions, as well as, internationally. - Multiple feasibility and impact studies for power projects in Oklahoma, Kansas, Texas, Vermont, Colorado, Louisiana, New Jersey, New Hampshire, Connecticut and New York, for clients such as the Southwest Power Pool, New York ISO and ISO New England and merchant power plant developers.
- Individual Pterra staff have even broader experience that those listed above. For a detailed project resume of individual personnel, please contact us today.
- Links to sample Pterra impact studies posted on the web:
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