How Wind and Solar Saved the UK £1.7 Billion in Gas Imports Since the Iran War: A Step-by-Step Guide

Overview

Since the onset of the Iran war in late February 2026, the United Kingdom has avoided an estimated £1.7 billion in gas imports, thanks to record-breaking electricity generation from wind and solar power. This analysis, based on data from the National Energy System Operator (NESO) and Carbon Brief, reveals how renewable energy has slashed the need for gas-fired generation and reshaped the country’s electricity mix. In this tutorial, we’ll walk through the key facts, calculations, and trends—step by step—so you can understand exactly how wind and solar achieved this milestone. Whether you’re a student, policy analyst, or energy enthusiast, this guide will equip you with the tools to replicate the analysis and interpret similar data.

Prerequisites

Before diving into the steps, ensure you have:

• Basic familiarity with energy units (e.g., terawatt hours, gigawatts).
• Access to public reports from NESO or Carbon Brief (optional, for deeper checks).
• Ability to interpret simple line charts or tables (provided in the original analysis).
• A calculator or spreadsheet for verifying numbers.

Step-by-Step Instructions

Step 1: Understand the Energy Context

The Iran war began in late February 2026, when the US and Israel launched attacks on Iran. This sparked a fossil-fuel price crisis, driving up the cost of gas imports. The UK, which imports a significant portion of its gas as liquefied natural gas (LNG), faced soaring bills. But during this period, wind and solar generation on the island of Great Britain (England, Scotland, and Wales) hit unprecedented levels. The key metric: from March 1 to the end of April 2026, wind and solar produced a record 21 terawatt hours (TWh) of electricity.

Step 2: Gather Key Data Points

To replicate the savings calculation, you need the following numbers from NESO and Carbon Brief:

• Total wind and solar generation (since the war started): 21 TWh.
• Average gas price during the crisis period: assume a high price equivalent to roughly £0.042 per kWh (derived from the £1.7 billion total for 41 TWh of gas). Specifically, 41 TWh = 41,000 GWh = 41,000,000 MWh. £1.7 billion / 41,000,000 MWh = £41.46 per MWh, or about 4.1 pence per kWh.
• Gas generation avoided: 41 TWh, which corresponds to about 34 LNG tankers (each tanker carrying ~1.2 TWh of gas).

Step 3: Calculate Avoided Gas Imports

The analysis compares actual renewable generation to the gas that would have been needed otherwise. Use this formula:

1. Determine the total gas generation that would have occurred if wind and solar were absent: assume that every unit of wind/solar displaces a unit of gas (in practice, some gas may be needed for grid stability, but the analysis assumes direct displacement).
2. Multiply the displaced gas (41 TWh) by the average cost of imported gas per TWh. Given the £1.7 billion figure, the calculator gives: 41 TWh × £41.46/MWh = £1,699,860,000 ≈ £1.7 billion.
3. Convert to LNG tankers: 41 TWh ÷ 1.2 TWh per tanker ≈ 34 tankers.

Tip: Use spreadsheet software to handle large numbers and verify with official reports.

Step 4: Analyze the Impact on Gas Generation

Wind and solar didn’t just avoid imports; they also slashed actual gas-fired generation. Compare monthly data:

• In March and April 2026, gas generation fell to the lowest levels ever recorded for those months.
• Year-on-year, gas output dropped by nearly one-third.

To check this, obtain NESO’s monthly generation figures for gas. For example, if gas generated 10 TWh in March 2025 but only 7 TWh in March 2026, that’s a 30% reduction. The original analysis shows this trend clearly in the second figure.

Step 5: Examine the Broader Electricity Mix Shift

The most striking change is the flip in the UK’s electricity mix. A decade ago, fossil fuels produced more than four times the electricity of wind and solar. Now, for 15 consecutive months (including the full winter of 2025-26), wind and solar have outpaced fossil fuels. During the war period, wind and solar generated more than twice as much electricity as all fossil fuels combined.

To visualize: look at the third figure in the original analysis, which shows monthly generation from fossil fuels (red) vs. wind/solar (blue). The blue line consistently rises above the red line since early 2025.

Step 6: Interpret the Records and Analysis

April 2026 set several records:

• Gas set electricity prices roughly 25% less often compared to April 2022 (when fossil-fuel prices spiked after Russia’s invasion of Ukraine).
• On 22 April, for half an hour (15:30 to 16:00), a record 98.8% of electricity on the main transmission grid came from zero-carbon sources.

These records demonstrate that high renewable penetration directly reduces the influence of expensive fossil fuels on electricity pricing and enhances grid stability.

Common Mistakes to Avoid

• Confusing GB with the whole UK: The analysis covers only Great Britain (England, Scotland, Wales), not the integrated system with Northern Ireland or the Republic of Ireland. Always verify geographic scope.
• Miscalculating savings: The £1.7 billion represents avoided import costs, not net savings after accounting for renewable subsidies or grid upgrades. Do not conflate the two.
• Ignoring time of day: The 98.8% zero-carbon record lasted only 30 minutes. Such peaks do not represent constant supply; baseload remains dependent on other sources.
• Assuming perfect displacement: In reality, some gas capacity must remain for backup. The analysis assumes every unit of renewable generation replaces a unit of gas, which oversimplifies grid operations.

Summary

Through record wind and solar output, the UK avoided £1.7 billion in gas imports from March to April 2026, slashed gas generation by a third, and achieved a historic flip in the electricity mix. By following these steps—understanding context, gathering data, calculating savings, analyzing generation trends, and recognizing records—you can replicate this analysis and apply it to future energy crises. The key takeaway: accelerated renewable deployment offers a direct and measurable shield against volatile fossil-fuel prices.