The right-sized solar partner for Illinois buildings.
EarthQuest designs, builds and maintains commercial solar PV and battery storage systems across Illinois. We specialize in the small and mid-size projects that new energy codes now require, and that most solar providers turn down.
What EarthQuest focuses on
The 2024 IECC puts solar on new commercial buildings in Illinois
Illinois's statewide energy code for commercial buildings is now based on the 2024 International Energy Conservation Code, which took effect on November 30, 2025. For the first time, most new commercial buildings over 5,000 sq. ft. must include on-site renewable energy, usually rooftop solar.
- On-site solar by floor area. The model code sets the minimum array size at about 0.75 watts (DC) per square foot of conditioned floor area. Owners who can't meet it on site can use the off-site alternatives, but those come with long-term contract requirements.
- Energy storage readiness. New buildings must either install battery storage or set aside the space and electrical infrastructure to add it later.
- Additions count too. Additions to existing buildings must meet the renewable requirement for the area being added.
- Design and permit documentation. Roof space, structural loads, conduit routing and inverter specs all need to be on the construction documents, ideally from the start of design.
Why code-driven systems are often small
| Conditioned floor area | Approx. minimum PV (DC) |
|---|---|
| 8,000 sq. ft. retail / office | ≈ 6 kW |
| 20,000 sq. ft. medical / mixed-use | ≈ 15 kW |
| 50,000 sq. ft. light industrial | ≈ 37.5 kW |
| 100,000 sq. ft. warehouse / school | ≈ 75 kW |
This is where EarthQuest comes in. Large solar EPCs are built for megawatt projects, and many won't take on a 10 kW or 40 kW code-compliance system. Those small projects are our specialty. We work as a dependable solar subcontractor for general contractors, electrical contractors and developers, from design through inspection.
Figures are illustrative, based on the model 2024 IECC prescriptive path. Exceptions, compliance paths and local amendments vary by jurisdiction. Chicago and some municipalities adopt their own versions. We'll confirm the requirements for your permit.
Custom solar solutions, built on local expertise
Every building, utility tariff and incentive stack is different. We engineer each system to fit the site, the budget and the code.
New Construction
Code-compliant solar and storage designed alongside the architect, MEP engineer and GC: solar-ready zones, structural coordination, conduit pathways, permitting and installation on the construction schedule.
Existing Buildings
Rooftop, carport and ground-mount systems for operating businesses, nonprofits and institutions that want to cut utility costs. We include a full roof and electrical assessment before we propose anything.
Operations & Maintenance
Monitoring, inspections, cleaning, inverter and optimizer troubleshooting, and repairs. We also service systems other installers built, including ones whose original contractor has gone out of business.
Incentives & Policy
Illinois Shines, Illinois Solar for All, ComEd and Ameren distributed generation and storage rebates, and federal tax credits. We know how Illinois renewable energy policy works and how to stack each incentive for the best return.
Solar plus storage is the new standard
Storage readiness is now part of the energy code, and Illinois utilities now offer dedicated rebates for batteries. Storage has become part of many commercial projects from the start.
- Lower demand charges. Batteries shave peak demand, often the largest part of a commercial electric bill.
- Resilience. Backup power keeps critical loads running during outages.
- Utility programs. Battery rebates and grid-service programs in ComEd and Ameren territory can add new revenue and offset upfront cost.
- Right-sized arrays. Pairing storage with a smaller array lets you use more of what you generate on site, so the system can be optimized instead of oversized.
Storage-ready vs. storage-installed
On new construction, we help owners decide whether to install a battery now or build the space, conduit and panel capacity to add one later. The answer depends on load profile, tariff, available rebates and budget, and we model all of them before you commit.
For existing buildings, we evaluate adding storage to current solar arrays or installing solar and storage together as one integrated system.
Straightforward from first call to final inspection
Assess
Site visit, utility bill and load review, roof and electrical evaluation, code requirements.
Design
Cost-effective engineering, equipment selection, incentive modeling and a clear, itemized proposal.
Build
Permitting, utility interconnection, installation and inspection, coordinated with your project team.
Maintain
Monitoring and maintenance that keep the system producing for its full 25+ year life.
Local, honest and focused on doing it right
EarthQuest Renewable Energy Systems, Inc. is an Illinois solar energy development company. Founder and President Jack Johannesson has worked in commercial solar sales and business development in Chicago since 2019, helping businesses, nonprofits and developers through the technical, financial and regulatory sides of going solar.
Jack's approach is simple. He encourages anyone considering solar to ask around and compare installers, because promises made before a contract don't always survive after it's signed. EarthQuest is built on telling customers how things really are, educating them, and earning a reputation for trust.
"At EQ, we aim to help bring more renewable energy into our communities by bringing expertise and passion to sustainability projects big and small, simple and complex."
Have a project that needs solar?
Whether it's a code-required system on new construction or an upgrade to an existing building, we'll give you a straight answer on what makes sense.
- Emailinfo@earthquestsustainability.com
- Service areaChicagoland & Northern Illinois