Solar Installation Procurement Contracts In New Zealand

What should your solar installation procurement contract actually cover?

If you're supplying panels, inverters, batteries, mounting gear or installation services, the answer is more than just price and delivery date. A good procurement contract helps you lock in the equipment, timing and responsibilities that keep your solar project moving.

Solar projects can get messy quickly when one part of the supply chain slips. A late inverter, a discontinued panel model or unclear subcontractor responsibility can hold up the whole job and leave you carrying costs you didn't expect.

The good news is that your contract can deal with these issues upfront. It doesn't need to be complicated, but it does need to be specific.

What Is A Solar Installation Procurement Contract?

A solar installation procurement contract is a written agreement that sets out how equipment, materials and related services will be supplied for a solar project.

Depending on your business model, it might be used with:

• panel, inverter and battery suppliers
• wholesalers or distributors
• installation subcontractors
• commercial customers buying a full solar system
• EPC-style project partners who manage engineering, procurement and construction

For a smaller residential installer, it may sit behind your customer contracts and supplier agreement terms. For a larger commercial solar business, it might be a detailed project document with technical schedules, delivery milestones and performance requirements.

Either way, the core job is the same. Your contract should make it clear what is being supplied, when it needs to arrive, what happens if something changes, how contract amendments are handled and who carries the risk if the project is delayed.

What Should A Solar Supplier Contract Include?

Your solar supplier contract should clearly describe the equipment, delivery obligations, warranties, terms of sale, payment terms and what happens if the supplier can't provide what was promised.

At a minimum, your contract should cover:

• Equipment specifications: the brand, model, wattage, capacity, compatibility and certifications for panels, inverters, batteries, mounting systems and monitoring hardware
• Quantities and packaging: how many units are being supplied and how they need to be packed, labelled and protected in transit
• Delivery dates: fixed delivery dates or milestone dates, plus any lead time assumptions
• Delivery location: whether equipment is going to your warehouse, directly to site or to a third-party logistics provider
• Risk and title: when ownership passes and who bears the risk of loss or damage during delivery
• Inspection rights: how long you have to check the equipment and report defects, shortages or damage
• Payment terms: deposits, progress payments, final payment, GST treatment and invoicing details
• Warranties: product warranties, workmanship warranties, performance warranties and any manufacturer-backed guarantees
• Substitutions: whether the supplier can substitute components and what approvals are needed
• Delay consequences: notice requirements, extension rights, credits, liquidated damages or termination rights

Make sure the contract lines up with your quotes to customers. If your customer quote promises a particular inverter or battery chemistry, your supplier contract shouldn't let the supplier swap it out for a materially different product without your approval.

A small mismatch can become a big problem. If your supplier's terms say they can substitute any equivalent product, but your customer contract locks you into a named component, you're the one caught in the middle.

What Happens If A Supplier Misses The Delivery Date?

If a supplier misses the delivery date, your rights depend on what your contract says and how critical that date was to the project.

Solar installation projects often have tight dependencies. Scaffolding may be booked, electricians may be scheduled, grid connection steps may be timed and your customer may have arranged site access around your programme.

Your contract should deal with late delivery before it happens. Useful clauses include:

• notice obligations: the supplier must tell you as soon as they become aware of a likely delay
• updated delivery plans: the supplier must provide a revised delivery date and mitigation plan
• priority allocation: your order must not be pushed behind later orders without your consent
• cost recovery: you can recover reasonable rebooking, storage, site attendance or demobilisation costs where appropriate
• liquidated damages: a pre-agreed daily or weekly amount for delay, if it's a genuine estimate and not a penalty
• termination rights: you can cancel all or part of the order if delay goes beyond an agreed long-stop date

Say Talia runs a solar installation business in Waikato. She orders batteries for a commercial customer and books her electrical subcontractor for the following week. The supplier then says the batteries are delayed by three weeks because a shipment was held up.

If Talia's procurement contract only says delivery is expected in June, she may struggle to recover the cost of rescheduling the subcontractor. If it says delivery is due by 14 June, delays must be notified within 24 hours and the supplier is responsible for agreed rebooking costs, she is in a much stronger position.

For larger projects, you may also want a project programme and heads of terms attached to the contract. This can show how equipment supply, site access, installation and commissioning all fit together.

Can A Supplier Substitute Solar Panels, Inverters Or Batteries?

Yes, a supplier can substitute components if your contract allows it, but you should control when and how substitutions can happen.

Component substitutions are common in clean energy supply chains. Models get discontinued, shipping changes, manufacturers alter specifications and distributors run out of stock.

The issue isn't whether substitutions ever happen. The issue is whether the replacement works for your project, your customer promise and your compliance obligations.

Your substitution clause should say that any replacement must:

• meet or exceed the original technical specifications
• be compatible with the rest of the system
• hold any required certifications or approvals for use in New Zealand
• not reduce system output, safety or warranty coverage
• not increase your installation labour or redesign costs unless agreed
• be approved by you in writing before dispatch or installation

You should also think about customer-facing promises. Under the Fair Trading Act 1986, you must not mislead customers about what they're buying. If your marketing says a customer will receive a specific brand or performance level, you need to make sure the installed system matches that claim or that the customer has clearly agreed to the change.

For residential and small customer projects, substitution can also affect trust. Even if the replacement is technically similar, a customer may be unhappy if they expected a premium brand and received something unfamiliar.

How Do Performance Warranties Work In Solar Projects?

Performance warranties work by promising that the system, or specific components, will meet certain output or degradation standards over time.

In solar projects, there are usually several warranty layers:

• manufacturer product warranties: covering defects in panels, inverters, batteries or other equipment
• performance warranties: covering expected energy output or panel degradation over a stated period
• installation workmanship warranties: covering the quality of installation work
• system performance commitments: covering how the full installed system should perform under agreed assumptions

Your procurement contract shouldn't simply say the supplier provides standard warranties. Ask for the actual warranty documents and make sure they match the project.

Check carefully for:

• who gives the warranty and whether they have a New Zealand presence
• how long the warranty lasts
• what is excluded, such as weather events, improper installation or grid issues
• whether labour, freight and removal costs are covered
• whether the warranty transfers to the property owner
• what records are needed to make a claim

You should also be careful with performance promises to customers. Solar output depends on factors such as panel orientation, shading, weather, degradation, site conditions and customer usage patterns.

If you give a performance guarantee, define the assumptions. For example, the contract might say output estimates are based on a particular design, no new shading, proper maintenance and normal weather patterns. Without those assumptions, you may be blamed for matters outside your control.

The Consumer Guarantees Act 1993 may also apply where you supply goods or services to consumers. Consumer services must be carried out with reasonable care and skill, be fit for purpose where the customer made that purpose known, and be completed within a reasonable time if no time is fixed. You generally can't contract out of the Consumer Guarantees Act for consumer customers.

For business-to-business supply, parties can sometimes contract out of the Consumer Guarantees Act if both are in trade and the contracting out is fair and reasonable. This needs to be done clearly in the contract.

Who Is Responsible For Installation Dependencies?

Responsibility for installation dependencies should sit with the party best placed to control them, and your contract should spell this out clearly.

Solar installations often depend on many moving parts, including:

• site access
• roof condition and structural suitability
• scaffolding or height access equipment
• electrical isolation and switchboard readiness
• network approvals or connection steps
• availability of licensed electrical workers
• customer shutdown windows
• weather and health and safety conditions

If these dependencies aren't allocated properly, you can end up responsible for delays you didn't cause.

Customer Dependencies

Your customer contract should explain what the customer must provide. This might include safe site access, accurate site information, permission to work in agreed areas and timely approvals.

If the customer doesn't meet those obligations, your contract should allow you to extend the project timeline and recover reasonable extra costs.

Supplier Dependencies

Your supplier contract should require suppliers to provide technical documents, warranties, compliance certificates and delivery updates on time.

If an inverter supplier fails to provide technical data needed for design sign-off, the contract shouldn't treat that delay as your fault.

Compliance Dependencies

Some work on solar systems will involve prescribed electrical work. In New Zealand, electrical work is regulated under the Electricity Act 1992 and associated electrical safety rules, and electrical workers must hold the right registration and practising licence through the Electrical Workers Registration Board.

Your procurement and subcontractor terms should require compliance with applicable electrical safety laws, the Building Act 2004 where relevant, the Health and Safety at Work Act 2015, and any project-specific safety requirements.

If the system includes monitoring software, customer portals or remote performance data, think about privacy as well. The Privacy Act 2020 may apply if you collect personal information, such as customer contact details, usage information or site data linked to an identifiable person.

Can You Use Subcontractors On A Solar Installation Project?

Yes, you can use subcontractors if your customer contract allows it and your subcontractor agreements clearly allocate responsibility, safety and quality obligations.

Subcontracting is common in solar projects. You might use electrical subcontractors, installers, scaffolding providers, engineers, logistics providers or monitoring software technicians.

Your contracts should answer three practical questions:

• Can you appoint subcontractors without customer approval?
• Are you still responsible to the customer for subcontractor work?
• What standards must subcontractors meet before they attend site?

From a customer perspective, you'll often remain responsible for delivering the project even if a subcontractor does part of the work. That means your subcontractor terms need to mirror the obligations you have promised to your customer.

For example, if your customer contract says installation must be completed by Friday and all workers must follow a site safety plan, your subcontractor agreement should require the same timeline and safety compliance.

Pay close attention to worker status too. Labels aren't enough. If you call someone a contractor but control them like an employee, the arrangement can create risk under the Employment Relations Act 2000.

The Employment Relations Amendment Act 2026 introduced a contractor gateway test to give more certainty around some contractor arrangements. Broadly, written terms, freedom to work for others, genuine control over when work is accepted and the ability to subcontract or organise work independently can all matter. If your solar business relies heavily on individual contractors, tailored advice is sensible because the practical working relationship is just as important as the wording.

Your subcontractor agreement should cover:

• scope of work and technical standards
• licences, registrations and competency requirements
• health and safety duties
• site rules and customer conduct
• insurance requirements
• defect rectification
• confidentiality and customer information
• payment milestones and invoicing
• who supplies tools, equipment and materials
• limits on further subcontracting

What Legal Rules Affect Renewable Energy Procurement Agreements?

Several New Zealand laws can affect renewable energy procurement agreements, especially when you supply to consumers, use standard terms or make performance claims.

The main ones to keep in mind are:

• Fair Trading Act 1986: your marketing, quotes and contract documents must not mislead customers about price, savings, output, equipment quality or warranties
• Consumer Guarantees Act 1993: consumer customers receive statutory guarantees for goods and services, and you generally can't contract out of these
• Contract and Commercial Law Act 2017: general contract rules may affect formation, cancellation and contractual remedies
• Privacy Act 2020: applies if you collect, use or share personal information through quotes, monitoring platforms or customer management systems
• Health and Safety at Work Act 2015: you need to manage work health and safety risks, especially for roof work, electrical work and multi-contractor sites
• Electrical safety rules: electrical work must be performed by appropriately registered and licensed people, with required certification handled properly

The Fair Trading Act also has unfair contract term rules. These can apply to standard form consumer contracts and standard form small trade contracts. A small trade contract can include a business-to-business contract with an annual value of $250,000 or less when the trading relationship starts.

This matters if you use take-it-or-leave-it standard terms with customers or smaller suppliers. Clauses that give you broad rights to change price, substitute equipment, avoid liability or cancel without a fair reason may need careful review.

Templates often miss these project-specific issues. A general supply agreement may not properly deal with solar warranties, installation dependencies, electrical compliance, network timing or component substitutions.

How Do You Make Your Procurement Terms Practical?

You make your procurement terms practical by matching them to how your projects actually run, not just how you hope they will run.

A useful way to do this is to map the project from quote to commissioning and ask where things can go wrong.

Step 1: Map The Supply Chain

List each party involved in the project. This may include manufacturers, distributors, delivery service providers, installers, electricians, engineers, software providers and the customer.

Then work out who controls each risk. For example, your supplier controls whether the correct inverter is dispatched, but your customer may control site access.

Step 2: Align Your Contracts

Your customer terms, supplier terms and subcontractor agreements should work together.

If your supplier has a 12-week lead time, don't promise your customer a 4-week installation unless you have stock in hand or a reliable alternative.

Step 3: Attach The Technical Details

Put key technical requirements in a schedule. This can include equipment lists, design assumptions, output assumptions, compliance standards and commissioning requirements.

Clear schedules reduce the risk of arguments about what was included in the price.

Step 4: Keep Records

Keep signed quotes, purchase orders, delivery records, serial numbers, warranty documents, installation photos, certificates and customer approvals.

These records help with warranty claims, compliance questions and future maintenance.

Key Takeaways

• A solar installation procurement contract should cover equipment supply, delivery timing, warranties, substitutions, payment and delay consequences.
• Component substitutions should require your written approval and must not reduce system performance, compliance or warranty protection.
• Delay clauses matter because late equipment can affect installation crews, site access, customer promises and project costs.
• Performance warranties should be tied to clear assumptions about design, shading, weather, maintenance and customer use.
• Subcontractor agreements should mirror your customer obligations and deal with safety, licences, quality and worker status.
• New Zealand laws such as the Fair Trading Act, Consumer Guarantees Act, Privacy Act and health and safety rules can all affect solar procurement terms.

If you'd like help with your solar procurement terms, supplier contracts, subcontractor agreements or customer-facing installation terms, you can reach us at 0800 002 184 or team@sprintlaw.co.nz for a free, no-obligations chat.