Split vs All-in-Two Solar Street Lights: Which Fits Your Project

What the two formats actually are

A split solar street light is the layout most people picture: a photovoltaic panel on its own bracket at the top of the pole, a luminaire on an arm aimed at the road, a battery in a box on the pole or buried at the base, and a controller at the pole base. Each element is a separate item that is mounted, wired and replaced on its own.

An all-in-two light folds three of those items together. The luminaire, the battery and the controller share one sealed head; only the solar panel is separate, on its own bracket, connected by a single cable. The pole therefore carries no external battery box, and the panel can still be tilted independently of the beam.

So the practical difference is not the panel — both formats separate it. It is where the battery lives, and how much of the system has to be opened when something needs attention.

Where the battery sits — the decisive difference

Heat is the main driver of lithium battery ageing, and the two formats place the pack very differently. In a split system the battery can be dropped to the pole base, shaded, put in a vented box or buried in the foundation chamber, where soil temperature stays well below air temperature through the afternoon peak. In an all-in-two head the pack shares a sealed housing with the LED array and its driver, a few centimetres from the hottest part of the assembly, at the top of a pole in full sun.

Where summer daytime temperatures reach 40 °C with little shade and the installation is expected to last a decade, that difference shows up in cycle life rather than in the first year’s performance. In a mild climate, or for a deployment measured in a few years, it narrows. If you need an all-in-two format in a hot region, ask what the head does about it — a slide-out pack, a vented or thermally separated battery compartment, a heat-spreading structure — rather than assuming it is handled.

Panel orientation and energy yield

Because the panel is a separate module in both formats, both allow it to be tilted to suit the site’s latitude while the luminaire is aimed where the light is needed. That is worth stating plainly, because an independently aimed panel is precisely what an all-in-one head cannot offer.

The two formats do differ in how much panel and battery they can carry. A split system takes the panel and the battery as separate line items, so a large array and a large pack can be specified for a high-output head on a wide carriageway. An all-in-two series is built around a defined panel size per model. The all-in-two range we source, for example, runs from an 18 W head on an 18 V 50 W panel up to a 60 W head on an 18 V 170 W panel, with batteries from 11.1 V 24 Ah to 11.1 V 63 Ah, 3,000 to 10,000 lm of output and mounting heights of 4 m to 12 m. If your lighting class needs more than that, the format points you back to a split system.

Installation, commissioning and service access

• Installation. An all-in-two light arrives as a head and a panel: one mechanical interface at the top of the pole, one cable run, sealed connections. A split system has more wiring, more glands and more torque checks, and therefore more skilled labour per pole.
• Commissioning. Both need the controller settings verified and recorded — profile, dimming schedule and low-voltage cut-off. On an all-in-two head those settings are usually reached through a remote control, an app or a sealed port. Confirm before ordering that the access route is not locked to the supplier, or the client loses control of the installation.
• Routine service. Panel cleaning and controller reads are similar. Battery replacement is not: on a split system the pack normally sits at the pole base, within reach from the ground, while on an all-in-two head the housing has to be opened — and possibly lowered — before the pack can be reached.
• Spares. A split system lets you hold one spare luminaire, one spare controller and one spare battery. An all-in-two head is a single assembly, so a controller fault takes the whole head off the pole.

Cabling, theft and exposure

A split installation exposes more copper between the panel, the battery and the luminaire, and in some regions that cable is itself the target. An all-in-two light exposes almost no cable, but the head is compact, valuable and removable, and its theft takes the light, the battery and the controller in one go. Both are managed the same way: tamper-resistant fasteners, welded or security fixings on the panel bracket, a buried or locked battery compartment where the format allows one, and a supervised location wherever one is available.

Which format suits which project

In practice many schemes mix the two: split systems on the main carriageway where lighting performance is contractual, and all-in-two lights on internal roads, residential streets, pathways and parking where a lower performance threshold applies and installation speed matters. Specification detail for both formats is in how to specify solar street lights in a tender, with pole and spacing decisions in pole height and spacing. Our solar street lights page lists the split and all-in-two ranges we source, and the street light poles page covers the columns they mount on.

Where all-in-one lights fit — a separate category

An all-in-one solar light is a different product family rather than a third option on this page. There the panel, the battery, the controller and the luminaire are all built into a single head, which makes it the fastest of the three to install and leaves the cleanest pole — but the panel angle is fixed by the angle that throws light onto the road, so energy harvest and light distribution compromise with each other. It is a strong answer where installation speed and appearance matter more than maximum output. We keep it as its own range rather than as a variant of a solar street light; the all-in-one solar lights range covers it.

How we can help

We are a China-based trading and project sourcing company, not a manufacturer. We review specifications and BOQs, match a product and configuration to your site conditions, source from qualified manufacturers, and manage quality through to pre-shipment inspection. If you are preparing a tender or specification and want a second opinion, contact us.