Power System Studies

Individual technical studies when you need specific analysis rather than a complete grid connection package.

Individual Studies Available

While we specialise in complete G99 compliance packages, we also offer individual power system studies for projects where specific analysis is needed. This includes:

  • Projects with partial study packages requiring gap-fill analysis
  • Industrial and commercial power systems outside G99 scope
  • Due diligence and technical review for project acquisitions
  • Design verification and independent checking
  • Troubleshooting and problem investigation

All studies are completed using industry-standard tools, primarily DIgSILENT PowerFactory, and delivered as comprehensive technical reports suitable for DNO submission or internal use.

Available Studies

Load Flow Analysis

Steady-state power flow calculations to determine reactive power capability and verify compliance with DNO active/reactive power (PQ/UQ) requirements.

Reactive capability assessmentPQ curve verificationVoltage regulation

Short Circuit Studies

Fault level calculations to determine equipment ratings, protection device selection, and network fault contribution from connected generation.

Switchgear ratingsFault infeed contributionMake/break capacity

Protection Coordination

Grading studies to ensure correct fault detection, discrimination, and clearance times across protection devices from generation to grid interface.

Relay settingsIDMT gradingUnit protection schemes

P28 Voltage Assessment

Analysis of voltage fluctuations caused by generation output changes per ENA Engineering Recommendation P28.

Rapid voltage change limitsFlicker assessmentStart-up transients

G5/5 Harmonic Studies

Harmonic distortion analysis per ENA Engineering Recommendation G5/5 including emission limits and filter design recommendations.

THD complianceIndividual harmonic limitsFilter sizing

Dynamic Stability

Time-domain simulations assessing transient response to network disturbances, fault ride-through, and control system performance.

LVRT/HVRT complianceFrequency responseControl interactions

Reactive Power Studies

Assessment of reactive power capability, voltage control performance, and compliance with Grid Code reactive requirements.

PQ capabilityVoltage controlReactive compensation

Earthing and Step/Touch

Earthing grid performance, rise of earth potential and step and touch voltages against the limits in EN 50522 and ENA TS 41-24.

Grid performanceRise of earth potentialStep and touch

Arc Flash

Incident energy, arc flash boundary and PPE category to IEEE 1584 or NFPA 70E, calculated off the same network model as the protection study, with the label data exported ready to print and a report on what to do about it. G99 does not require it, but EPCs and developers increasingly ask for it alongside the connection package.

Incident energy and boundaryPPE category and labelsRecommendations report

Software & Tools

We use industry-standard software accepted by UK DNOs and network operators.

DIgSILENT PowerFactory
ETAP
PSCAD
In-house Tools

Cable rating and thermal calculations run on our own software, maintained in step with the IEC standards, which is what makes the turnaround fast. See cable system design.

Frequently Asked Questions

Can I commission individual studies rather than a full package?

Yes. While we offer complete G99 packages, individual studies are available when you need specific analysis only. This is common for projects with partial study packages from other consultants, or for non-G99 applications.

What software do you use?

We primarily use DIgSILENT PowerFactory for power system analysis, which is widely accepted by UK DNOs. We also use specialist tools for cable sizing, protection coordination, and harmonic analysis as required.

Do you work on industrial power systems?

Yes. Grid connections for renewable generation are the bulk of it, but industrial power systems are a lane in their own right: load flow, short circuit, protection coordination and relay settings for factories, refurbishments and sites with no current settings schedule.

Do you do arc flash?

Yes. Incident energy, the arc flash boundary and the PPE category come off the same network model as the protection study, to IEEE 1584 or NFPA 70E, with the label data exported ready to merge and print and a report setting out what we recommend doing about it. Because the model is already built for the grading, arc flash is a small step rather than a new project, which is why it usually sits inside a connection or protection package. Two things we do not do. Site inspection, so the equipment data has to come from you or from a survey carried out by someone else. And training. Both are specialist work in their own right and we will say so rather than stretch to cover them.

Can you review or verify studies completed by others?

Yes. We provide independent technical review services for studies completed by other consultants or in-house teams. This is common for due diligence, project acquisition, or quality assurance purposes.

Discuss Your Study Requirements

Tell us about your project and the studies you need. We'll confirm scope and provide a fee proposal.

Discuss a Study

Tell us what you need looked at and we will come back with a scope. Chartered Engineer led, and we take individual studies as well as complete packages.

Or call 07951 651 013 or email enquiries@stardeltapower.co.uk