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Understanding Design-Bid-Build in Solar Projects Delivery

• Updated on March 9, 2023 • [rt_reading_time postfix=”minute”] read

In recent articles, we’ve been looking into three of the main project delivery methods offered by solar companies. We’ve covered design-build and EPC in previous blogs, so for this one we’ll turn our attention to the design-bid-build project delivery method.

Read on to learn more about how the design-bid-build process works and how it compares to design-build.

Table of Contents

The Design-Bid-Build Method

A Construction Industry Norm

Design-bid-build (DBB) is the traditional go-to delivery method that’s been used by the construction industry for hundreds, if not thousands of years. Also known as the design-tender project delivery method, with a DBB project you act as the general contractor. That means you have complete control over the entire construction process – from finding and managing the vendors to assuming the majority of the risks associated with the delivery of the project.

Here’s how it works.

The Three Phases of Design-Bid-Build

As its name suggests, there are three distinct phases in the design-bid-build method.


In the first phase of the design-bid-build process, the project owner (you) hires a company to design a solar system. The designer will translate your vision into engineering and construction drawings that outline system specifications, and all the information potential vendors and suppliers will need to provide you with a quote.


Once you have the complete design documents, you need to hire contractors to actually turn the vision into reality. You’ll send the plans out to vendors and suppliers, asking them to participate in the bidding process (this is also known as the tendering process). You’ll need electricians, software specialists, energy storage experts, mechanical engineers, construction contractors, and other professionals with significant previous experience in the solar industry.

Often, the bids you’ll get back will include the cost of both labor and materials, though in some cases, you may want to source materials directly from a supplier.

At this point, your project can take one of two paths:

Begin the Construction Phase

In an ideal world, you’d approve the final design and decide which bids you want to accept after just a single round of the design-bid process. Once you sign separate contracts with each vendor, the construction of your renewable energy system can begin.

Refine Your Design

One-round and done is not typical however. Something usually comes up in the bidding process that sends you back to the design phase. Perhaps you want to add a feature or change the specifications on your solar panels. Maybe you need to find a way to bring down overall project costs. Either way, if you need to refine the scope of work, you’ll need to enlist the designers to update their plans and drawings.

Once your solar system design has been tweaked to meet your new specifications, you’ll need to re-bid all aspects of the project. A minor design tweak in one area could mean significant changes in another and you don’t want to discover that half way through the construction process.

You’ll carry on with this rinse and repeat process until you’ve crafted what you think will be the perfect system and you sign a contract with each vendor. The construction process cannot begin until you’ve achieved this milestone and you may spend considerable time managing this back and forth.


Since you’ve assumed the role of general contractor, the construction phase can take a significant amount of your time. You’ll need to manage each of the contractors, fielding any questions they may have and making sure that they deliver on the project as agreed upon.

In the end, you will have had a hand in every aspect of your new solar energy system.

A Linear Approach

As you can see, the design-bid-build method is a very linear approach. There’s no overlap between the phases; you’re either in design, in the bidding process, or your solar system is being built. This methodology has both advantages and disadvantages.

Transparent and Potentially Lower Costs

Because the design and bids are locked in before construction begins, you’ll have a complete understanding of all the costs involved in building your solar project. Plus, the competitive bid process inherent to design-bid-build could reduce the total cost of your project. Of course, it’s important to keep in mind that you often get what you pay for and going for the lowest bid might not be the best option – and you can’t forget to account for the cost of your time to manage the project.


For some construction projects, design-bid-build can be an advantage because you’re able to select the vendors you think are best suited for each portion of the installation. The construction industry includes many sub-specialties, and for certain types of projects, it may be important to hire a vendor that only focuses on one specific aspect of a project, say for example, a plumbing company.

With design-bid-build, each vendor plays to its strengths.

Of course, this is not as critical when it comes to solar installations, as solar construction itself is a specialization. Rather than finding a vendor to install the racking system and another to do the wiring, odds are you’ll find providers that handle most aspects of the actual construction. Where this gets complicated is if your site needs to be reinforced or modified in any way – you’ll likely need to source a separate vendor for that work.

Longer Timelines

The linear nature of the design-bid-build process means that the amount of time it takes to deliver your completed solar system can be longer than it is with other delivery methods. As noted above, there is no overlap between the design-bid-build phases, and thus no economies of scale to be gained.

Limited Flexibility

Design-bid-build projects are flexible, but only to a point. Once you’ve finalized the design and accepted the bids, it’s very difficult to make changes. Change orders implemented during the construction phase of a design-bid-build project are typically time consuming and expensive.

Complete Control, But All the Headaches

As the project owner of a design-bid-build project, you have oversight over all aspects of the construction process. While that means you retain control over the execution, it also means that you’re responsible for any snags or challenges that arise – and the more complex your solar system, the harder it will be to manage. For example, if your interconnection doesn’t pass inspection, you’ll have to work with your electrical vendor to rectify things.

You’ll also have to manage the inevitable finger pointing and blame shift that happens between vendors when something on the project goes awry.

solar epc

Another Option: The Design-Build Project Delivery Method

If you’re a busy business owner or facility manager, there’s a good chance you’re thinking I just don’t have the time to commit to being the general contractor on the company’s solar construction projects. That’s another full-time job!

Don’t worry, you’re not alone.

Fortunately, there’s a new kid in town and his name is design-build.

The Birth of Design-Build

The design-build project delivery method is gaining momentum in the construction industry, among leading solar providers, and with business owners because it’s turnkey, flexible, customizable, and streamlined.

If you read our article on the engineering, procurement and construction (EPC) project delivery method, you’ll know that one of its most attractive features is the fact that it’s turnkey – you hire one company, and they take care of the rest. But, like design-bid-build, EPC has its challenges, namely it’s not very flexible. With EPC, you have to buy an entire solar package, whether you want the whole thing or not.

Enter the nimble design-build method, which takes the best of EPC and design-bid-build to create a solution that’s flexible, customizable, and perfect for companies that want to invest in solar energy but not the hassles of becoming a general contractor.

Design-build is EPC 2.0

Design-build uses the same basic framework as the EPC model. You have a single contract with a company that’s in charge of the engineering, procurement, and construction of your solar project. You don’t have to manage separate contracts for each provider like you do with design-bid build.

But, design-build throws away the rigidity of EPC and allows you to pick the services you want and have them delivered on your timeline, just like you can with design-bid-build. The difference is that your design-build team manages the entire process for you.

Your Design-Build Team

When you work with a design-build company, the majority of the team members working on your project will be on staff. Leading solar companies that favor this project delivery method, like Velo Solar, have engineering, design, construction, software, energy storage and solar system optimization experts in house.

The use of sub-contractors is minimized and if any are needed, your design-build team will find them, manage the bid process, and they’ll sign the contract documents, not you.

Collaboration Leads to Good Things

Collaboration is the name of the game with the design-build method. Your team works closely with you and each other to make sure that everyone is aligned on your needs, goals, and the best way to execute on the delivery of your solar system.

The collaboration between the project owner and the design-build team continues across the entire life of the project. Yes, this means that you’ll need to set aside some time to participate in the process, but it will be nowhere near the number of hours that would be required if you went with the design-bid-build method and were your own general contractor.

The upside is that design-build projects typically have fewer change orders once construction starts. This is because everyone on the team is contributing during the design phase of the project, so potential issues can be spotted much earlier on.

That said, should something come up during construction that requires a redesign, having your entire design-build team on the case makes implementing those changes much easier and quicker.

It also should be said that the inherent collaboration found with the design-build process eliminates finger pointing between vendors should something go wrong. Your solar partner is fully responsible for ensuring the success of your project and managing any issues that might arise.

Design-Build is Customizable and Streamlined

Projects commissioned under the design-build method tend to lead to long-term partnerships between the provider and the customer. This is a good thing because it means you have a partner that can meet you wherever you are on the path to solar energy integration and move with you at your unique pace.

The design-build method is a more streamlined process than you’d get with a design-bid-build project. Because the entire project is being managed by a single team, project management is simplified.

Design-Build Saves You Time and Money

It should be pretty clear at this point that a design-build approach will save you time, especially when compared to the design-bid-build method. Your design-build partner will take on most of the time-consuming work associated with the installation of a solar project, including project management and paperwork.

Saving you time also saves you money, because after all, your time is incredibly valuable. Working with a single provider is often less expensive than sourcing each aspect of the construction project from a different vendor. Think about it it this way: you could spend countless hours wading through bids and learning how to be your own general contractor on a solar project, or you can hire a team of experts to do it for you. Realistically, the latter will be much more cost effective.

Design-build projects also typically have a shorter timeline, should you choose to move forward with installing the full solar system at once. This is because design-build allows for some overlap between the design and construction phases. Construction on a design-build project can begin while the design team is still finalizing some aspects of the design, and that simply can’t happen with design-bid-build.

Design-Bid-Build vs. Design-Build

Design-bid-build has its place in the construction industry. There’s a reason it’s the most common project delivery method.

But when it comes to solar, you can do better.

Working with a design-build provider like Velo Solar will ensure that you get a solar system that meets your needs, on your timeline, and without the headaches of other project delivery methods.