Top 10 Best Solar Energy Consulting Services of 2026

AECOM is a consultancy that executes end-to-end solar planning work that typically includes solar irradiance modeling, energy yield assessment, and shading and layout evaluation for site candidates. The service mix regularly extends into utility interconnection study scoping and construction-oriented engineering deliverables, which reduces handoff friction when feasibility must progress toward detailed engineering design. Fit is strongest when a single accountable firm must connect geospatial site screening inputs to electrical single-line diagram development and permitting package coordination.

A key tradeoff is that AECOM delivery is engineering and documentation heavy, so teams expecting a lightweight analytics workflow or rapid self-serve reporting may find the process slower than specialized modeling boutiques. A common usage situation is a utility interconnection study plus early design package for a developer that needs consistent assumptions across resource, yield, electrical design, and grid impact scope.

DNV fits teams that need defensible modeling assumptions and engineering review trail across distributed generation and utility-scale studies. Deliverables commonly align to project planning needs such as energy yield assessment, shading and layout impact evaluation, and specification-level guidance that supports later electrical and construction design phases. Strong governance shows up when projects require consistent technical methods across stakeholders like developers, lenders, utilities, and permitting authorities.

A tradeoff appears when internal teams want highly agile, iterative workflows without heavy documentation overhead. DNV performs best when the project timeline can absorb formal study cycles and review checkpoints, such as utility interconnection study scoping and production forecast signoff for bankability narratives.

Arup’s work pattern emphasizes integrated engineering analysis rather than standalone photovoltaic system design. Solar feasibility studies commonly combine solar irradiance modeling, shading analysis, and energy yield assessment inputs that feed design iterations and commercial case work. Grid engagements connect technical plant design assumptions to utility interconnection study needs, which reduces late-cycle rework when scope expands. Engagements typically work best when stakeholders require documented technical basis, disciplined assumptions, and cross-discipline coordination from site through electrical interfaces.

A tradeoff appears in speed of turnarounds because engineering depth and documentation increase cycle time compared with lighter feasibility vendors. Arup fits situations where project milestones depend on defensible inputs for utility processes, structural and electrical constraints, or land and permitting coordination. It also fits owners who want consistent engineering interpretation across rooftop feasibility study details or utility-scale layout and interconnection inputs.

Jacobs delivers solar energy consulting across project planning, engineering, and grid-facing studies with staffing that typically spans technical due diligence and owner-side design coordination. Solar resource assessment, production forecast work, and site-specific engineering support are handled alongside permitting and permitting package assembly for distributed generation and utility-scale scopes.

WSP delivers solar consulting work that converts site constraints into engineering deliverables for project planning and grid studies. Core capabilities include solar resource assessment, photovoltaic system design support, shading and energy yield evaluation, and interconnection-focused grid impact analysis for distributed generation.

TRC Companies is a solar energy consulting provider focused on project planning work like feasibility studies, engineering support, and grid-related assessments. The firm’s typical engagement covers energy yield assessment, site screening, and design inputs used to support permitting and interconnection planning.

Tetra Tech differentiates itself through end-to-end engineering and advisory depth that spans resource modeling, grid studies, and permitting support for solar projects. The firm’s core capabilities typically cover solar resource assessment, photovoltaic system design, and energy yield assessment work products used in planning, financing, and interconnection steps.

NV5 delivers solar energy consulting that centers on project planning support across engineering, permitting coordination, and grid-facing studies for distributed and utility-scale efforts. The firm is distinct in how it packages feasibility work around interconnection and site constraints, then carries technical output forward into design and documentation workflows.

Burns & McDonnell delivers solar energy consulting focused on utility-scale and commercial projects that need grid coordination, permitting support, and engineering-backed feasibility work. The firm supports geospatial site screening through its assessment workflows and turns results into engineering documentation used for early design and interconnection planning.

Ramboll delivers solar energy consulting that couples feasibility studies with engineering depth for grid-facing and built-environment constraints. The work typically spans solar irradiance modeling, energy yield assessment, and shading analysis that feeds into photovoltaic system design and project planning deliverables.