North America
Microgrid and energy software for North American projects
HOMER was developed at the National Renewable Energy Laboratory in Colorado. It has been the standard tool for North American microgrid, BESS, and renewable project modelling for over 30 years. From ERCOT ancillary service stacking to Alaskan village diesel displacement, from IRA §48E ITC optimisation to First Nations off-diesel community projects — HOMER is built for the complexity of this market.
The North American energy context
The United States operates the world's second-largest electricity system, fragmented across seven ISOs and RTOs — CAISO, ERCOT, PJM, NYISO, ISO-NE, MISO, and SPP — plus large non-RTO territories across the Southeast, the Western Interconnection outside California, and Alaska. Each market has a distinct capacity design, ancillary services stack, and transmission access regime. The 2022 Inflation Reduction Act (IRA) is the single most consequential energy policy of the decade: §48E ITC, §45Y PTC, transferability under §6418, and direct pay under §6417 have reshaped the financial model for every BESS, solar, wind, and hybrid project in the country.
Canada brings a different structure: 70%+ non-emitting electricity already on the grid, driven by hydro dominance in British Columbia, Quebec, Manitoba, and Newfoundland & Labrador. Provincial fragmentation is the defining feature — BC Hydro, Hydro-Québec, AESO (Alberta), IESO (Ontario), and smaller territorial operators in the Northwest Territories, Yukon, and Nunavut each operate under different rules. The federal Clean Electricity Regulations target a net-zero grid by 2035. Canadian ITCs — Clean Technology (30%), Clean Electricity (15%), and Clean Technology Manufacturing — are materially different from IRA mechanics but comparably consequential.
Across both countries, HOMER's heritage use case remains strong: over 500 federally recognised Tribes in the US and 200+ remote off-grid First Nations and Inuit communities in Canada depend on diesel for power. Diesel displacement modelling — HOMER Pro's core capability since 1993 — is as relevant in a Nunavut hamlet in 2025 as it was in a Guatemalan village in 1995.
Four ways HOMER serves North America
1. Utility-scale BESS and hybrid renewables — HOMER Front
North American BESS revenue stacking is market-specific. In ERCOT, the only revenue streams are real-time energy and ancillary services (ECRS, RRS, Reg-up, Reg-down) — no capacity market exists. In CAISO, Resource Adequacy under the Slice-of-Day framework anchors value, with AS and energy on top. PJM, NYISO, ISO-NE, MISO, and SPP each layer capacity market revenues differently, and each defines its regulation, spinning reserve, and operating reserve products with distinct settlement rules. HOMER Front models all seven ISO/RTO market designs, incorporating real-time and day-ahead price sequences and clearing probabilities for AS products — see the dedicated guide to ancillary services and incentive modelling across North American ISOs.
IRA mechanics compound the revenue modelling requirement: §48E ITC (standalone storage eligible, technology-neutral from 2025), domestic content bonus (10 percentage points), energy community bonus (10 percentage points), low-income community allocation, transferability to third parties, and direct pay for tax-exempt entities. HOMER Front computes the post-credit IRR and NPV alongside the pre-credit dispatch optimisation.
In Canada, AESO's Energy Storage market and IESO's Long-Term 1 RFP (2.5+ GW awarded) represent the two most active BESS procurement channels. HOMER Front models both alongside hydro+BESS hybrid configurations in British Columbia and Québec.
2. Commercial and industrial behind-the-meter — HOMER Grid
US commercial electricity prices and demand charge structures vary by utility territory, but the economics of behind-the-meter solar-plus-storage are compelling across most markets. HOMER Grid models C&I sites against half-hourly TOU rates, demand charges, and state-level incentive stacks: California SGIP, New York VDER + Bulk Storage Incentive, New Jersey SuSI, Massachusetts SMART and Clean Peak Energy Standard, Hawaii 100% RPS programmes.
Data centres are the fastest-growing load category in North America. Virginia's Northern Virginia cluster (Dominion Energy territory) has grid interconnection queues backed up multi-year for new hyperscale capacity. Texas under ERCOT draws AI hyperscaler build-out. Quebec hydro — cheap, low-carbon, cool-climate — is courting hyperscalers as a US alternative. HOMER Grid models on-site generation, BESS resilience, and PPA structuring against site-specific load profiles and tariff structures.
EV charging infrastructure under NEVI (National Electric Vehicle Infrastructure program) funding, ZEVIP (Canada), and state and provincial programmes represents a new load category that reshapes C&I demand curves. HOMER Grid handles EV load profiles alongside on-site generation dispatch.
3. Resilience microgrids and federal facilities — HOMER Grid and Pro
California PSPS (Public Safety Power Shutoff) events have driven the largest wave of community microgrid development in US history. HOMER models the solar-BESS configurations underpinning these projects, including critical load prioritisation and extended islanding duration requirements. Hurricane-corridor microgrids in Florida, Texas, and the Gulf Coast face a different risk profile — HOMER Pro models both planned islanding and unplanned grid-outage scenarios.
US Department of Defense installation resilience is one of HOMER's established verticals. MILCON (Military Construction) funding for microgrid projects at Fort Bliss, Marine Corps Air Station Miramar, JBLM, Tyndall AFB, and dozens of other installations references HOMER-generated analyses. VA hospitals, university campuses (under sustainability and resilience mandates), and federal facilities under GSA management are comparable buyers.
4. Off-grid, remote, and Indigenous community microgrids — HOMER Pro
HOMER was designed at NREL to answer one question: what is the least-cost hybrid system for a remote diesel-powered community? That question remains equally live in 2025. In Alaska, the Alaska Energy Authority's (AEA) Renewable Energy Fund and Power Cost Equalization (PCE) program have financed diesel displacement projects in over 200 remote villages — the majority modelled using HOMER Pro. In Hawaii, non-interconnected island systems on Molokai, Lanai, and Hawaii Island face diesel displacement economics under a state 100% RPS target.
In Canada, the federal Indigenous Off-Diesel Initiative, Wah-ila-toos, and Clean Energy for Rural and Remote Communities (CERRC) programs are funding off-diesel transitions in 200+ remote First Nations and Inuit communities in the Northwest Territories, Nunavut, Yukon, Northern Ontario, Northern Quebec, Labrador, and BC interior. HOMER Pro's outputs — net present cost, LCOE, diesel savings, CO₂ reduction — align with the reporting requirements of these funding programs.
Deep dive
Ancillary services, regulation, and incentive modelling across ISOs
Regulation, energy, and capacity products are settled differently in each ISO, and state programmes such as Massachusetts Clean Peak and the New England ConnectedSolutions programme overlay structured obligations on wholesale participation. The dedicated guide breaks down each ISO’s regulation mechanics, what HOMER Front models directly through its four revenue-stream types, and where reserves, frequency response, and ramping fit as market context.
Read the ancillary services and incentive modelling guideNorth American country pages
Selected North American projects
Revenue stacking across ERCOT ancillary services
A 100 MW / 200 MWh BESS project used HOMER Front to optimise dispatch across ECRS, RRS, Reg-up, Reg-down, and real-time energy markets. Multi-year price scenarios produced the confidence intervals that project finance lenders required for debt sizing.
Solar+storage under California SGIP and NEM 3.0
A commercial real estate operator modelled a 2 MW PV array with 1.5 MWh BESS across three California properties under SGIP incentive tiers and NEM 3.0 / NBT export compensation. HOMER Grid identified a $1.2 million NPV improvement over grid-only supply across the portfolio.
Installation microgrid under MILCON resilience programme
A US military installation in the hurricane corridor used HOMER Pro and HOMER Grid jointly to size a solar-BESS-generator microgrid for critical facility resilience. The design achieved 72-hour islanding duration for essential loads with a 15% reduction in annual diesel consumption.
Diesel displacement under Alaska Renewable Energy Fund
For a 340-person Alaska village relying on diesel generation at $1.20+/kWh delivered cost, HOMER Pro sized a wind-solar-BESS-diesel hybrid that reduced diesel consumption by 68% and cut LCOE from $0.72 to $0.31/kWh. The AEA Renewable Energy Fund application referenced HOMER outputs directly.
Off-diesel transition under Indigenous Off-Diesel Initiative
A remote First Nations community in Northern Ontario used HOMER Pro to evaluate solar-BESS integration with the existing diesel plant. The CERRC program grant application was supported by HOMER outputs demonstrating a 55% diesel reduction and 18-year NPV positive under conservative diesel price assumptions.
Long-Term 1 RFP project under IESO capacity auction
A Canadian IPP used HOMER Front to model a 200 MW / 800 MWh BESS project under IESO's LT1 RFP framework, stacking capacity contract revenues with ancillary services participation. The analysis validated the project's bid-in price and informed the optimal duration configuration.
HOMER in North America — the origin story
HOMER was developed at the National Renewable Energy Laboratory (NREL) in Boulder, Colorado, beginning in 1993. The original brief was to produce a techno-economic optimisation tool for remote off-grid hybrid power systems — the kind of diesel-dependent communities across Alaska, the American Southwest, and developing markets that had no practical way to compare diesel-only against diesel-plus-renewables.
HOMER Energy LLC was spun out of NREL in 2009. UL Solutions acquired HOMER Energy in 2020. The Boulder team — the same people who built HOMER's core simulation engine — continues to develop the product today, now under UL's global energy testing and certification infrastructure.
This lineage is not incidental. It means HOMER's algorithms were written by the same researchers whose work underpins NREL's System Advisor Model (SAM) and whose published papers define the academic standard for microgrid techno-economic analysis. No competitor carries this credibility.
UL Solutions in North America
Northbrook, Illinois
UL Solutions global headquarters.
Boulder, Colorado
HOMER Energy product team. NREL campus neighbours. The home of HOMER since 1993.
Toronto and Ottawa, Canada
UL Solutions Canadian operations serving energy, safety, and certification markets.
San Jose, Research Triangle, Atlanta, and others
Additional UL Solutions US offices serving regional energy and industrial clients.
North America use case guides
Battery storage modeling for North America
ERCOT, CAISO, PJM, NYISO, ISO-NE, MISO, AESO, IESO — with IRA
Energy modeling for North American data centers
Virginia, Texas, Phoenix, Pacific Northwest, Quebec
Ancillary services and incentive modelling across ISOs
Regulation, capacity, Clean Peak, ConnectedSolutions — ERCOT to IESO
Ready to model your North American project?
Whether you are sizing a BESS project for ERCOT, evaluating a First Nations off-diesel transition in Nunavut, or modelling a data centre on-site generation strategy in Northern Virginia, HOMER gives you the techno-economic analysis to make confident decisions.