A data-driven guide for renewable energy investors, fund managers, and deal teams

Over the past decade, more than $380 billion has been deployed into European wind capacity alone. Yet in 2025, an acute wind drought cut renewable energy revenue by 10–20% across almost half of Europe — a reminder that most renewable energy investment cases are still built on the climate of the past, not the climate of the future.

This guide shows how climate change is quietly eroding renewable energy returns through three channels — wind resource drift, solar heat degradation, and physical damage — and how leading renewable energy investors are turning climate risk into a capital-allocation decision instead of a blind spot.

Inside this guide you'll learn:

• How the 2025 European wind drought exposed a systemic gap in renewable energy resource models
• The three vectors quietly eroding renewable energy IRR — and how to price them
• Real portfolio modelling showing up to 1.65% IRR variation and €22m in returns from climate risk alone
• How to turn resilience into a capital-allocation decision, and defend your exit valuation
• How EarthScan Energy helps renewable energy investors stress-test assets against a changing climate

Download your free copy now and see exactly where climate risk is eroding returns in your renewable energy portfolio.

FAQs

What is "Hidden IRR" in renewable energy investing?
Hidden IRR is the return impact that emerges when future climate conditions diverge from the historical assumptions embedded in a renewable energy investment case — a gap that conventional resource assessments and risk heatmaps don't consistently capture.

How much can climate risk actually affect renewable energy returns?
In Mitiga's modelling of four comparable wind farms in Spain, climate-related wind variation alone drove a 1.65% unlevered IRR difference and €22 million in gross returns over a 25-year hold — before degradation, physical damage, or insurance effects were added.

What are the main ways climate risk erodes renewable energy IRR?
‍Three channels: wind resource drift (the P50 assumptions behind wind assets shifting over time), solar thermal degradation (heat accelerating panel ageing and raising LCOE), and physical damage events such as hail, which can generate outsized, concentrated losses.

Is this a compliance issue or an investment issue?
An investment issue. Climate risk enters the same cash flows that determine renewable energy production, operating costs, debt capacity, insurance, and terminal value — it isn't a separate ESG overlay.

How can renewable energy investors act on this at acquisition, hold, and exit?
By climate-sensitising yield assessments, translating physical hazards into financial metrics like Average Annual Loss, treating resilience capex as its own investment case, and using documented climate sensitivities to defend exit valuations.

What is EarthScan Energy?
EarthScan Energy is Mitiga Solutions' climate-risk and energy-performance platform, purpose-built for solar PV, wind, and grid infrastructure. It processes 40+ energy-relevant climate variables at sub-kilometre resolution to help renewable energy investors price, design, and stress-test assets against a changing climate.

Ready to see what's eroding your renewable energy returns?

Download the free guide and get a clear, evidence-based view of how climate risk affects renewable energy portfolios — and what to do about it.