RIO
Regional Investment & Operations
The only energy model capable of truly representing the economics of deeply decarbonized energy systems across all sectors. RIO extends the framework of a highly temporally resolved capacity expansion model past electricity planning to an economy-wide representation — electricity, pipeline gas, hydrogen, liquid fuels, heat, and transport — identifying least-cost pathways while capturing the critical interactions between sectors.
Proven in the Highest-Profile Analyses
RIO has been the analytical engine behind the majority of national decarbonization analyses conducted in the past decade.
U.S. & European editions
Annual Decarbonization Perspective
Our flagship research series modeling economy-wide pathways for the U.S. and Europe, informing federal policy and corporate strategy.
Princeton University
Net-Zero America
The landmark national analysis mapping five distinct pathways to net-zero emissions by 2050, with unprecedented spatial and technological detail.
Princeton ZERO Lab
REPEAT Project
Rapid Energy Policy Evaluation Toolkit — real-time modeling of federal energy and climate legislation, including the Inflation Reduction Act.
Princeton & University of Melbourne
Net-Zero Australia
Modeling national and international impacts of Australian decarbonization across energy, industry, and land use sectors.
NJ, MA, WA, and more
State Energy Plans
State-level decarbonization roadmaps including the New Jersey Energy Master Plan, Massachusetts Decarbonization Roadmap, and Washington State Energy Strategy.
Fortune 500 clients
Utility & Corporate Analyses
Long-term resource planning and decarbonization strategy for major utilities and corporations navigating the energy transition.
What Makes RIO Different
Economy-Wide Optimization
RIO extends the framework of a highly temporally resolved capacity expansion model past electricity planning to an economy-wide representation — co-optimizing across electricity, pipeline gas, hydrogen, liquid fuels, heat, and transport in a single solve.
Unprecedented Sector Coupling
Rather than treating sectors in isolation, RIO captures the critical interactions between them. Sector coupling — not just electricity storage — is the key to cost-effective renewables integration. Hydrogen complements electrification rather than competing with it.
Highest Temporal & Spatial Resolution
Hourly dispatch across multi-decade planning horizons with multi-region spatial resolution. This granularity is essential for accurately valuing flexible resources, long-duration storage, and variable renewables.
Technology Representations Others Miss
From Allam-Fetvedt cycle power plants and iron-air batteries to electrified direct iron reduction for steel, Fischer-Tropsch synthetic fuels, and Tokamak fusion — RIO models technologies that other platforms don't even have categories for. Hydrogen pathways span PEM, SOEC, and AEM electrolyzers to methane pyrolysis and geologic hydrogen. Storage ranges from liquid air (LAES) and gravity-based to thermochemical metal oxide systems. Nuclear includes SMRs, molten salt reactors, and sodium-cooled fast reactors.
Integrated Demand-Side Optimization
Endogenous demand optimization including technology adoption, energy efficiency, fuel switching, and flexible load capabilities — capturing the full value of demand-side resources alongside supply.
Policy & Market Fidelity
Models complex energy and climate policies with significant detail — clean energy standards with REC tracking, hourly clean energy matching, emissions caps, carbon pricing, and technology-specific incentives like IRA tax credits.
Unprecedented Optimization Scope
RIO simultaneously optimizes across 15 resource categories in a single solve — capturing interactions that siloed models miss.
Utility-Scale Renewables
Hydroelectric & Pumped Hydro
Thermal Generation with CCS
Hydrogen Production & Salt Cavern Storage
Biomass Gasification & Conversion
Geologic Carbon Sequestration
Direct Air Capture (Solvent & Sorbent)
Electricity Storage (Li-ion to Iron-Air)
Zero-Emission Vehicles & Fleets
H₂ & CO₂ Pipeline Infrastructure
Electric Transmission & Distribution
Distributed Energy Resources
Synthetic Fuels (Fischer-Tropsch, SAF)
Industrial Decarbonization (DRI, LC3)
Thermal & District Energy Networks
How RIO Is Used
Market Sizing
How big is the addressable market for a technology under different policy and technology scenarios?
Competitiveness Assessment
At what cost targets does a technology become competitive? What are the key performance thresholds?
Market Prioritization
Which regions, sectors, or applications represent the highest-value entry points?
Feature Evaluation
How much is a specific technology attribute (flexibility, duration, efficiency) worth to the system?
Deployment Forecasts
What deployment trajectories are consistent with cost-optimal system evolution under realistic constraints?
Technology Target Development
What R&D targets would unlock the most system value? Where should innovation investment focus?
Questions Only RIO Can Answer
The hardest energy questions span sectors, timescales, and technologies simultaneously. Here are insights from our recent analyses that required RIO's economy-wide scope.
What happens when data centers need more power than the grid can deliver?
Data center demand could increase U.S. electricity costs 8% nationally while extending coal plant retirements and raising near-term emissions 30% by 2030. Load is arriving faster than clean generation — making siting, flexibility, and procurement strategy critical.
Under Pressure & Data Center Emissions Through 2040
Is battery storage enough for a renewable grid?
As renewable penetration increases, the binding constraint shifts from power capacity to energy duration. Gigawatt-hours, not gigawatts, become the reliability bottleneck — and sector coupling often outperforms batteries alone.
Duration Is All You Need
Is summer still the season grid operators should worry about most?
Winter peak demand now rivals or exceeds summer peaks on renewable-heavy grids. This seasonal inversion fundamentally alters resource adequacy — planning built on historical summer-centric assumptions is increasingly misaligned.
Winter Is the New Summer
Is there one right answer for transmission expansion?
Machine learning can generate hundreds of viable routing alternatives under varied assumptions. Geography constrains some corridors but leaves surprising flexibility in others — revealing options that single-path optimization misses entirely.
From Here to There
Do policy rollbacks doom the energy transition?
Ensemble modeling reveals dozens to thousands of near-optimal pathways that persist even under policy uncertainty. Technology cost trajectories and market forces create momentum that single-scenario analysis dramatically underestimates.
How OBBBA Rewrites America's Energy Transition
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