Lead Times: How Do You Quote a Project You Cannot Yet Order?

Published by Quinn Lai | By InverPower Technical Team

Published 22 August 2026 · Last updated 22 August 2026

A quotation is a promise about a programme as much as a price. The part that breaks is rarely the price — it is the assumption that the equipment specified in March can be delivered in June. Anyone who quoted through the last few years of shipping disruption learned that the hard way, and the lesson has a short half-life.

Four things drive the variance

Four things, and they compound. Whether the item is held locally or has to be imported, which is the single largest factor. How popular the model is, since a range everybody specifies runs down faster than a niche one. Where it sits in its product cycle, because a model approaching replacement gets scarce before it disappears. And shipping — vessel schedules, port congestion and customs clearance all add variance rather than a fixed number of days.

Two Malaysian factors sit on top. Utility-scale construction pulls volume out of the market a year or two after a large tender, and East Malaysian deliveries add a sea leg and inland transport that is measured in weeks rather than days.

Local stock and imported stock are different promises

Equipment held in a Malaysian warehouse can be confirmed as a quantity and reserved. Equipment on a purchase order to a factory is a forecast, and the honest way to describe it is as an estimate with a source. That distinction belongs in the quotation, because a client planning around an energisation date needs to know which of the two they are relying on.

Local stock is not automatically faster in every case — a large order can exceed what is held, and a special variant may never be stocked at all. What local stock reliably provides is certainty, and certainty is what a programme is built from.

There is a quieter benefit to buying from stock as well: what arrives is what was quoted. Long import chains are where substitutions creep in — a different power class because the original is discontinued, a revised model number, a variant with a different frame. Each of those is a change to a design that has already been approved, and catching it at delivery is far better than catching it on the roof.

Quoting around it

Planning backwards from an energisation date

Where a client has a hard deadline — a tenancy, a reporting period, an incentive window — work backwards and be honest about each step. Commissioning and the licensee's process sit at the end and are not under the contractor's control. Installation duration comes from the crew and the site access. Delivery to site comes before that, and the order has to be placed before it, against confirmed availability.

Two habits protect the deadline. Order the long-lead items first rather than the whole bill of materials at once, since the critical path is usually one or two lines rather than everything. And identify a substitute for each of those lines before it becomes urgent — a second acceptable inverter model, checked against the string design, is worth having in the file whether or not it is ever used.

The conversation with the client

Say what is stocked and what is not. Clients accept a delivery window that is explained far more readily than a date that slips, and an EPCC who says a particular model is on a longer lead time and offers an alternative reads as someone who is managing the project rather than hoping.

It also protects the quotation. A validity period with a stated reason — prices and availability change — is much harder to argue with three months later than a bare date, and it gives you a clean reason to requote rather than absorbing a change.

Storage deserves its own line in that conversation. Battery systems generally carry longer and more variable lead times than modules or string inverters, and on a project where storage is part of the scope it is usually the item that sets the date. Quote it as such rather than folding it into a single delivery window for everything.

Asking for current figures

Any number printed in an article about lead times is out of date by the time it is read, which is why there are none here. InverPower holds Sungrow inverters and storage, Trinasolar modules and the balance of system in Malaysia, and can tell you what is physically on the shelf today and what the current position is on anything that has to be brought in. Send the bill of materials with the dates you are working to, and we will come back with what is stocked, what is not, and what the realistic window looks like.

Frequently Asked Questions

How far ahead should an EPCC order for a fixed energisation date?

Work backwards from the date through the licensee's process, commissioning, installation and delivery, then place the order for long-lead items against confirmed availability rather than an estimate. The habit matters more than a rule of thumb, because the constraint moves between product categories.

Is local stock always faster?

Usually, and not always. A quantity larger than what is held, or a variant that is not stocked, will still be imported. What local stock provides reliably is certainty — a confirmed quantity you can reserve, rather than a forecast.

Should lead times be stated in the quotation?

Yes, as a window with the stock position behind it, alongside a validity period. It manages the client's expectation and it gives you legitimate grounds to requote if the position changes, which a bare price does not.

What if the specified model becomes unavailable mid-project?

Have the substitute identified in advance and checked against the design — string sizing, mounting, protection and monitoring all have to still work. Agreeing a substitution route in the contract is easier than negotiating one under time pressure.

Sources

• Sungrow — inverter and storage product ranges and documentation — https://www.sungrowpower.com
• Trinasolar — module ranges and documentation — https://www.trinasolar.com
• PETRA — large-scale solar programme announcements, which shape equipment demand cycles — https://www.petra.gov.my
• SEDA Malaysia — register of approved solar PV inverters, which constrains substitution — https://www.seda.gov.my
• Royal Malaysian Customs Department — import procedures affecting delivery timelines — https://www.customs.gov.my

Related InverPower posts:

• Where Do EPCCs Source Solar PV Components in Malaysia?
• Structuring a Solar Quotation: How Much Detail Should the Client See?
• Staged Payments: How Should Solar Milestones Be Defined in the Contract?