Accounts Payable Specialist

About Flatiron Energy

Flatiron Energy is developing and building grid scale standalone energy storage assets that integrate renewable energy onto the grid, replace fossil fuel plants, and increase grid reliability. Founded by a team of experienced energy storage experts, Flatiron has a demonstrated track record of developing critical infrastructure needed to achieve our reliability and energy climate goals. The team has deep experience in developing, constructing, and operating energy storage assets in wholesale markets. Flatiron is a portfolio company of Hull Street Energy and has significant committed capital for its growth plans.

We are a growing company with a dynamic, fast-paced, challenging, creative, fun, start-up culture. The right candidate will be excited to help build the company from the ground up, recognizing the challenges and opportunities for growth inherent in such a role. The Flatiron team is passionate about fighting climate change while ensuring their projects have an equitable impact on surrounding communities. Flatiron is only looking for candidates who resonate with our mission.

Title: Accounts Payable Specialist

Reports To: Controller

Location: Denver strongly preferred, New York / Boston / Remote possible.

Description: The Accounts Payable Specialist is responsible for managing and processing the company’s outgoing payments accurately and on time. This role ensures that all vendor invoices, expense reports, and payment transactions are properly recorded, approved, and reconciled in accordance with company policies and accounting standards.

Key Responsibilities:

• Review, verify, and process invoices, expense reports, and payment requests.

• Match purchase orders, invoices, and receiving documents (three-way match).

• Track spend by contract/purchase order/service agreement.

• Enter and maintain accurate vendor and payment data in the accounting system.

• Prepare and process check runs, wire transfers, and ACH payments.

• Reconcile accounts payable transactions and resolve discrepancies promptly.

• Respond to vendor inquiries and maintain positive vendor relationships.

• Assist with month-end closing by ensuring all expenses are recorded in the correct period.

• Maintain proper documentation and filing for all accounts payable records.

• Support audits and provide required documentation when requested.

• Ensure compliance with company policies and internal controls.

• Other duties as assigned

Key Qualifications

• Education: Associate’s or Bachelor’s degree in Accounting, Finance, or related field (preferred).
• Experience: 1–3 years of accounts payable or general accounting experience.
• Skills:
• Proficiency with accounting software (e.g., Bill.com, Expensify, Sage Intacct).
• Strong attention to detail and accuracy.
• Excellent organizational and time management skills.
• Knowledge of basic accounting principles (U.S. GAAP).
• Ability to communicate effectively and work in a team environment.
• Strong problem-solving skills, resourcefulness, creativity, and leadership skills
• Understanding of energy markets, particularly ISO-NE, NYISO, and PJM
• Strong interpersonal skills and the ability to build relationships with key stakeholders
• Superior verbal and written communication skills and high level of attention to detail

Compensation and Benefits:

• Job Type: Permanent, Full-time
• Salary: Competitive base salary commensurate with experience
• Bonus: Competitive bonus based on the achievement of milestones and performance
• Benefits: Flatiron offers an excellent benefit package with health care, dental, vision, and other health and wellness benefits. A 401 K with company matching is provided.