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P Project 2025 — Scenario 1

Purpose

This run package compares the national results of three target scopes across three model versions:

  • N Only
  • N+P
  • P Only

Each scope is evaluated under:

  • Old Retention
  • New Retention
  • New Retention + Differentiation

The framing comes directly from the comparison workbook title: "Impact of Retention & Differentiation Updates".

Source files

Master comparison workbook

Master Comparison Workbook

Main analysis file with measure groups, national totals, measure detail, coastal results, and lake-area breakdowns.

Download comparison workbook

How workbook links behave

The `.xlsx` files are published and clickable. In a browser they will normally download or open in your spreadsheet application rather than render as web pages.

Individual result workbooks

Target scope Old New New + Differentiation
N Only N Only Old retention.xlsx N Only New retention.xlsx N Only with New retention and Differentiation.xlsx
N+P N&P Old retention.xlsx N&P New retention.xlsx N&P with New retention and Differentiation.xlsx
P Only P Only Old retention.xlsx P Only New retention.xlsx P Only with New retention and Differentiation.xlsx

Quick downloads

N Only

N+P

P Only

National results

Values below are transcribed from sheet 1. National Totals in the master comparison workbook. Costs are shown in mDKK/yr, reductions in tons/yr, and area in 1,000 ha.

Scope Version Cost Δ vs Old Δ vs New N reduced P reduced Total area
N Only Old Retention 480.238 — — 13,794.6 10.2 595.7
N Only New Retention 480.849 0.611 — 13,789.3 13.7 635.3
N Only New Ret. + Diff. 481.223 0.985 0.374 13,789.3 13.6 633.6
N+P Old Retention 743.452 — — 14,046.4 76.8 760.3
N+P New Retention 739.875 -3.577 — 14,033.4 78.9 792.7
N+P New Ret. + Diff. 741.529 -1.923 1.654 14,038.3 78.8 790.5
P Only Old Retention 299.504 — — 1,324.9 68.6 227.4
P Only New Retention 299.355 -0.149 — 1,428.0 68.6 227.3
P Only New Ret. + Diff. 299.237 -0.267 -0.118 1,431.1 68.7 227.3

Main findings

  • New Retention lowers national cost in N+P by 3.58 mDKK/yr relative to Old Retention, while increasing total P reduction by roughly 2.12 tons/yr.
  • In N Only, the cost effect is negligible, but the selected measure area jumps by about 39.6 kha under New Retention.
  • Adding Differentiation has a small national effect in N Only (+0.37 mDKK/yr vs New Retention) and a moderate one in N+P (+1.65 mDKK/yr), but slightly lowers cost in P Only (-0.12 mDKK/yr vs New Retention).
  • P Only still generates substantial N side-effects: about 1.32–1.43 kt N/yr depending on retention version.

Cost structure by measure group

Values below are from sheet 2. Cost by Measure Group in the master comparison workbook, shown in mDKK/yr.

Scope Group Old New New + Diff.
N Only Temp N measures 113.443 119.470 118.351
N Only Perm N measures 342.320 316.140 318.905
N Only Infrastructure 24.431 45.204 43.924
N+P Temp N measures 104.451 109.912 108.705
N+P Perm N measures 505.294 478.296 481.196
N+P P measures 15.233 15.309 15.256
N+P Combined N+P 4.731 4.718 4.744
N+P Infrastructure 113.744 131.639 131.628
P Only Perm N measures 186.785 186.668 186.292
P Only P measures 15.644 15.654 15.703
P Only Combined N+P 4.859 4.877 4.827
P Only Infrastructure 92.216 92.156 92.415

Interpretation

  • The retention update shifts spending from Perm N measures toward Infrastructure in both N Only and N+P.
  • P Only is not a pure P-measures portfolio in cost terms. It is still dominated by Perm N measures and Infrastructure.

Highest-cost measures

These are the top five measures by annual national cost from sheet 3. Measure Detail.

Scope Version Top-cost measures
N Only Old Retention FO (135.1), WL (124.8), EC (70.0), LRh (57.3), CCS (33.7)
N Only New Retention FO (135.3), WL (98.6), EC (74.7), LRh (55.8), MW(VP3) (43.0)
N Only New + Diff. FO (139.4), WL (100.1), EC (72.5), LRh (53.1), MW(VP3) (41.7)
N+P Old Retention FO (221.9), LRh (139.4), WL (120.4), MW(VP3) (70.7), EC (65.0)
N+P New Retention FO (230.7), LRh (130.3), WL (92.9), MW(VP3) (88.3), EC (69.7)
N+P New + Diff. FO (218.6), LRh (143.7), WL (94.6), MW(VP3) (87.0), EC (67.4)
P Only Old Retention LRh (111.1), FO (75.7), MW(VP3) (49.8), Overflow (22.2), PWET (12.7)
P Only New Retention LRh (111.0), FO (75.6), MW(VP3) (49.8), Overflow (22.2), PWET (12.7)
P Only New + Diff. LRh (110.9), FO (75.3), MW(VP3) (49.8), Overflow (22.4), PWET (12.7)

Numbers are mDKK/yr.

Coastal result hotspots

These summaries are derived from sheet 4. Coastal Catchments in the master comparison workbook.

Largest coastal cost shifts when moving from old to new retention

Scope Largest increases Largest decreases
N Only Isefjord, indre +5.00 mDKK, Jammerland Bugt og Musholm Bugt +4.93 mDKK, Rødsand og Bredningen +3.47 mDKK Ringkøbing Fjord -10.45 mDKK, Knudedyb -7.34 mDKK, Grådyb -4.01 mDKK
N+P Isefjord, indre +5.01 mDKK, Jammerland Bugt og Musholm Bugt +4.82 mDKK, Rødsand og Bredningen +3.46 mDKK Ringkøbing Fjord -10.46 mDKK, Knudedyb -7.50 mDKK, Grådyb -4.00 mDKK
P Only Nakskov Fjord +0.006 mDKK, Kås Bredning og Venø Bugt +0.002 mDKK, Det sydfynske Øhav +0.002 mDKK Roskilde Fjord, indre -0.046 mDKK, Lillebælt, Bredningen -0.033 mDKK, Randers Fjord, indre -0.026 mDKK

Where the differentiation step matters most

  • In N Only, the largest incremental coastal changes from adding differentiation on top of new retention occur at Isefjord, indre (-1.02 mDKK), Ringkøbing Fjord (+0.85 mDKK), and Knudedyb (+0.59 mDKK).
  • In N+P, the strongest differentiation response appears at Thisted Bredning (+1.26 mDKK), Isefjord, indre (-1.04 mDKK), and Ringkøbing Fjord (+0.86 mDKK).
  • In P Only, differentiation barely changes coastal costs. The largest absolute effect in the workbook is Smålandsfarvandet, syd at -0.139 mDKK.

Interpretation

  • The spatial pattern is highly uneven. A small number of coastal catchments absorb multi-million-DKK shifts when retention assumptions change.
  • Those cost shifts occur with almost no visible change in the reported coastal N reductions for the same catchments, which suggests the main effect is portfolio reallocation rather than target failure or large changes in delivered N.
  • P Only is spatially much less sensitive at the coastal-cost level than N Only or N+P.

Lake result hotspots

These summaries are derived from sheet 6. Lake - Area by Measure. Units differ by measure: ha for land measures, m for trees, and no. for mini-wetlands.

N+P: largest lake-level reallocations from old to new retention

Measure Largest lake-level changes
Trees Tissø +1900 m, Rands Fjord +1900 m, Tystrup Sø +1500 m
FO Arresø +1166 ha, Tange Sø -1014 ha, Glenstrup Sø +1013 ha
LRh Arresø -1152 ha, Hestholm Sø -1144 ha, Stadil Fjord +1067 ha
NPB20 Rands Fjord -248 ha, Jels Oversø +218 ha, Vejlen +204 ha
MW(VP3) Kær Vig +250, Torbenfeld Sø +50, Rugård Søndersø -30

P Only: largest lake-level reallocations from old to new retention

Measure Largest lake-level changes
Trees Rands Fjord -2700 m, Nakskov Indrefjord +2100 m, Nordby Sø -600 m
NPB20 Rands Fjord +111.7 ha, Skanderborg Sø -42.5 ha, Søgård Sø v. Herlufmagle -37.4 ha
PPC Stilling-Solbjerg Sø +20.46 ha, Jølby Nor -15.36 ha, Hejlskov Sø +8.32 ha
FO / LRh swap Sø v. Keldernæs FO -11.12 ha and LRh +11.12 ha; Flægen v. Eskør Inddæmning FO -8.52 ha and LRh -9.80 ha
MW(VP3) Kornerup Sø -30, Østerild Fjord -20, Bryrup Langsø -20

Interpretation

  • The lake-side response is more reallocation-heavy than the national totals suggest. Large local swings can hide behind small national cost changes.
  • In N+P, the strongest shifts involve FO, LRh, tree measures, and selected NPB20 reallocations.
  • In P Only, some lake catchments show strong substitution between lake-relevant measures even though total national cost barely moves.

Figures

National comparisons

Total cost — National cost comparison by target scope and model version. Total cost

Differentiation effect — Visual summary of the incremental effect of adding differentiation. Differentiation effect

Total area — Total selected area or units by target scope and version. Total area

Comparison graphics

New vs Old — Lollipop comparison of N and P outcomes after the retention update. New vs Old

Diff vs New — Lollipop comparison of N and P outcomes after adding differentiation. Diff vs New

Spatial diagnostics

Coastal cost distribution — Spatial distribution of coastal costs across catchments. Coastal cost distribution

Catchment cost changes — Where costs rise and fall under the updated assumptions. Catchment cost changes

Lake P area by measure — Lake-level allocation of P-relevant measures. Lake P area by measure

Lake trees distribution — Spatial distribution of tree allocations in the lake-focused results. Lake trees distribution

Additional figures

Cost change vs old Cost change vs old

Cost by group Cost by group

Cost per kg P Cost per kg P

Cost per kg N Cost per kg N

Measure costs Measure costs

Coastal scatter Coastal scatter

Coastal N reduction scatter Coastal N reduction scatter

Lake PWET distribution Lake PWET distribution

P gap distribution P gap distribution

N gap distribution N gap distribution

Area change — LRh Area change LRh

Area scatter Area scatter

Area boxplot Area boxplot

Area change — FO Area change FO

Area change — WL Area change WL

N/P scatter — New vs Old NP scatter New vs Old

Area change — MW Area change MW

N/P scatter — Diff vs New NP scatter Diff vs New

Caveats

  • This ingest documents workbook outputs as delivered. It does not yet verify every national result against underlying .gdx files or rerun the model.
  • Catchment-level and lake-level sheets are present in the raw workbooks but are not yet summarized exhaustively here.
  • The scenario package mixes target scopes and retention variants inside one project run folder, so this page should be read as a structured result digest rather than as a single model scenario in the narrower wiki/scenario-template sense.