Which connection dates slip least?
This page shows which connection dates in NESO’s TEC register were pushed back least often within a year. We group them by technology, transmission owner, status, size and connection year. A connection date due soon is far more likely to be pushed back than one that’s years away, so for each group we compare how many were pushed back with how many we’d expect from how far ahead they were. For how often connection dates move year by year, see Delays and exits. The figures on this page update with each new register.
Who this page helps, and how
Investors comparing projects. Two projects with the same connection date aren’t equally safe. Weigh each connection date by its group’s record here.
Developers planning a programme. Use the first chart to see how often connection dates as far ahead as yours are pushed back within a year.
Lenders and insurers. Use each group’s share pushed back as the base rate for delay assumptions and cover.
1. How far ahead the connection date was
Does it matter how far ahead a connection date is? Yes, more than anything else on this page. Across the full years from 2021 to 2025, 19.4% of the connection dates we compared were pushed back within the year, by a median of 17 months. Of those due within the year, 40.1% were pushed back, and 34.1% of those due the year after, but only 5.8% of those five years or more ahead. A connection date already past at the start of the year was pushed back 46.3% of the time, by a median of 31 months. In 2026 so far, 9.1% of the 1,721 connection dates compared have been pushed back.
How often connection dates were pushed back, by how far ahead they were
Full years 2021 to 2025 together; how far ahead is measured from the start of each year.
| How far ahead | Compared | Projects | Pushed back | Share pushed back | Median months pushed back |
|---|---|---|---|---|---|
| Past its connection date already | 188 | 138 | 87 | 46.3% | 31 |
| Due that year | 294 | 242 | 118 | 40.1% | 18 |
| The year after | 399 | 322 | 136 | 34.1% | 16 |
| Two years on | 387 | 330 | 99 | 25.6% | 15 |
| Three or four years on | 861 | 484 | 223 | 25.9% | 13 |
| Five years or more on | 1,848 | 1,085 | 107 | 5.8% | 22 |
| All connection dates | 3,977 | – | 770 | 19.4% | 17 |
What it means: The nearer a connection date, the likelier it is to be pushed back.
How we measured it
For each year we compare each project’s next connection date at the start of the year with its connection date at the end, as Delays and exits does: only projects with MW still to connect and a connection date at both points count, and a move of a month or more later is pushed back. A connection date’s distance ahead is its year against the year it was compared in. The year still running is left out of the chart, the table and the key figures, as its connection dates have had less time to move. A project can be compared in more than one year and at more than one distance ahead, so the Projects column counts it in each row and isn’t added up for all connection dates.
2. By technology, transmission owner, status, size and connection year
Which projects have their connection dates pushed back least? Comparing the share pushed back isn’t fair on its own: as the first chart on this page shows, connection dates due soon are pushed back far more often, and some groups have more of them. So for each group, we use the rates in the first chart to work out how many of its connection dates we’d expect to be pushed back, given how far ahead they were. Then we compare that with how many actually were: 1.0 means as many as expected, below 1.0 fewer.
For example, of the 1,311 storage connection dates we compared, we’d expect about 261 to be pushed back. 186 were, 0.71 times as many, the lowest of any technology. Of the technologies with 300 or more connection dates compared, offshore wind was highest, at 1.33 times: 71 pushed back where we’d expect about 53.
By transmission owner, NGET was lowest, at 0.94 times the number expected, and SHET highest, at 1.15 times. By size, projects under 50 MW were lowest, at 0.83 times, and projects of 1,000 MW or more highest, at 1.27 times.
We don’t rank substations. Most have too few projects to judge: only 2 of the 1,020 had ten or more projects compared.
Connection dates pushed back, against the number expected
1.0 means as many as we’d expect from how far ahead they were; below 1.0, fewer.
| Technology | Compared | Projects | Pushed back | Expected | Share pushed back | Median months pushed back | Times the number expected |
|---|---|---|---|---|---|---|---|
| Storage | 1,311 | 641 | 186 | 261.1 | 14.2% | 15 | 0.71 |
| Hybrid | 1,072 | 497 | 159 | 164.1 | 14.8% | 24 | 0.97 |
| Thermal | 215 | 69 | 68 | 63.6 | 31.6% | 20 | 1.07 |
| Solar | 139 | 55 | 40 | 33.2 | 28.8% | 15 | 1.20 |
| Onshore wind | 756 | 235 | 220 | 177.5 | 29.1% | 16 | 1.24 |
| Offshore wind | 380 | 118 | 71 | 53.3 | 18.7% | 12 | 1.33 |
| Other | 104 | 45 | 26 | 17.1 | 25.0% | 15 | 1.52 |
What it means: Storage connection dates have been pushed back least, against the number expected.
How we measured it
For each group, the number expected is how many of its connection dates would have been pushed back had each been pushed back as often as all connection dates the same distance ahead, at the rates in the first chart (full years 2021 to 2025 together). We divide the number pushed back by the number expected: 1.0 is as many as expected, below 1.0 fewer. Groups are ranked by that figure, lowest first; a group of fewer than 30 connection dates compared is listed after the rest, not ranked. Each connection date counts in the group its project was in at the start of the year: its technology, transmission owner, the status of its next stage, its MW still to connect and the year of its next connection date. Connection years are listed in date order, not ranked.
What if your connection date is pushed back?
QueueQuant values your project across thousands of possible futures for its connection date and the market, and tells you whether to hold, cut MW, sell or walk away, and what would change that answer.
How to cite this page
You’re welcome to quote our figures, charts and findings with this credit:
QueueWatch by QueueQuant, ‘Which connection dates slip least?’, queuequant.com/queuewatch/dates-that-slip-least/ (data to 3 November 2026). Contains data from NESO’s TEC register. Supported by National Energy SO Open Data.
Supported by National Energy SO Open Data. Registers from 29 January 2021 to 11 August 2026 are copies NESO released to QueueQuant on 19 October 2026 under the Environmental Information Regulations 2004 (request FOI/26/226). Later registers are QueueWatch’s own downloads from NESO’s Data Portal.