Arch Solar and SolarEdge Bring Solar Savings to Milwaukee's Affordable Housing Project
Multi-building portfolio powers affordable housing and community library with 38% energy offset
Arch Solar and SolarEdge Bring Solar Savings to Milwaukee's Affordable Housing Project
Multi-building portfolio powers affordable housing and community library with 38% energy offset
Solar Savings, ROI & Production
- Year 1 Production: 221.5 MWh annually
- Year 1 Utility Savings: $35,441
- Energy Offset: 38.43% of portfolio consumption
- Payback Period: 7.1 years
- Lifetime Savings: $1.68 million
Equipment specs
- Inverters: (2) SolarEdge SE50K Inverters + (4) SolarEdge SE10K Inverters
- Power Optimizers: 135 x SolarEdge P1101 Dual-Input Power Optimizers, 82 x SolarEdge S650b Dual-Input Power Optimizers
- Modules: 346 Boviet 545W Solar Modules
Installer Insight
We chose SolarEdge for ease of installation, clear monitoring visibility, and consistency across multiple sites in the portfolio. The longer string capabilities with SolarEdge power optimizers reduced our balance of system costs significantly—fewer homerun cables, less conduit, and reduced labor. Managing three separate buildings with different configurations becomes much simpler when you have a unified portfolio that delivers cost savings and reliable performance at each location.
Andrew Holmstrom
Business Development Supervisor, Arch Solar
Leading Developer Powers City's Affordable Housing Solar Initiative
Arch Solar, a leading solar developer in the Milwaukee market, partnered with the City of Milwaukee on this multi-building portfolio to produce on-site renewable power while helping offset utility costs for low-income apartments and community resources in an underserved neighborhood. With extensive experience in municipal and affordable housing projects, Arch brought proven expertise in managing complex, multi-site installations that serve community equity goals.
HIGHLIGHTS: Multi-building portfolios require flexible inverter sizing, unified monitoring across sites, and balance of system cost optimization—all enabled by SolarEdge's scalable product portfolio with extended string lengths.
The Challenge
Delivering Affordable Energy to Mixed-Use Community Portfolio
The apartment complex and library are located in a low-income area and the city has a mission to make housing affordable for families of all sizes and incomes, including units allocated for reduced rent. Reducing energy costs was critical to maintaining affordability.
The project faced unique implementation challenges:
- Multi-Building Complexity: Three separate buildings with different electrical meters, mixing residential apartments and public library use, required coordinated design and flexible inverter solutions.
- Cost Optimization Imperative: As an affordable housing project, every dollar saved on installation costs translated directly to better housing affordability and faster payback for the community investment.
- Evolving Construction Plans: Working on new construction meant adapting to changing design plans as the site progressed. The system needed adjustment to accommodate unexpected or field-relocated obstructions as buildings took shape.
- Community Impact Priority: As a city-supported affordable housing initiative, maximizing energy savings and demonstrating transparent performance were essential to serving residents and justifying public investment.
The Solution
SolarEdge Flexible Inverter Portfolio + Extended String Design
Arch Solar deployed a tailored mix of SolarEdge inverters—two 50kW units for the larger apartment buildings and four 10kW units for the smaller library building—leveraging dual-input power optimizers to create longer strings and reduce balance of system costs.
Key features:
- Extended String Lengths: Dual-input power optimizers enabled longer strings with fewer homerun cables back to inverters, significantly reducing wire runs, conduit requirements, and installation labor across all three buildings.
- BoS Cost Reduction: Fewer strings and longer wire runs meant reduced balance of system costs in combiner boxes, disconnect switches, and electrical materials—critical savings for an affordable housing project budget.
- Flexible Inverter Sizing: Mix of SE50K and SE10K inverters matched each building's specific capacity needs, optimizing performance across varied rooftop spaces without over- or under-sizing equipment.
- Unified Portfolio Monitoring: Single SolarEdge platform provides consistent monitoring across all three buildings and separate meters, simplifying operations and maintenance for the property management team.
- Adaptable Design: SolarEdge’s DC optimization and modular architecture allowed the team to adjust layouts as construction plans evolved, accommodating field changes without redesigning the entire system.
Benefits
Significant Savings Support Housing Affordability Mission
Key benefits include:
- Reduced Installation Costs – Longer strings with power optimizers cut balance of system expenses, maximizing budget for affordable housing
- 38% Energy Offset – Solar covers more than one-third of portfolio electricity consumption across apartments and library
- $35,441 First-Year Savings – Immediate utility bill reduction with $1.68 million in lifetime savings projected
- 7.1-Year Payback – Fast ROI enables long-term affordability for low-income residents
- 221.5 MWh Annual Production – Consistent clean energy across three-building portfolio
- Unified Management – Single monitoring platform simplifies operations across multiple buildings and meters
- Community Stewardship – Visible commitment to sustainability in underserved neighborhood
Community Impact
This project is part of a broader City of Milwaukee initiative to produce on-site renewable power while directly reducing utility costs for affordable housing residents. The solar arrays serve both low-income apartment units—including a designated percentage allocated for reduced rent—and the community library, demonstrating how clean energy can support social equity goals.
Arch Solar’s development partners continue to include solar in their portfolio, with additional collaborative projects anticipated in Milwaukee's underserved communities.
Environmental Savings
This PV system produces energy equivalent to:
