{ "id": 90016, "date": "2026-06-28T00:00:00", "date_gmt": "2026-06-28T00:00:00", "guid": { "rendered": "https:\/\/genixenergy.com.ua\/?p=90016" }, "modified": "2026-07-05T22:05:19", "modified_gmt": "2026-07-05T14:05:19", "slug": "ac-coupled", "status": "publish", "type": "glossary", "link": "https:\/\/genixenergy.com.ua\/en\/glossary\/ac-coupled\/", "title": { "rendered": "AC-coupled" }, "content": { "rendered": "

In an AC-coupled solar-plus-storage system, the solar inverter converts DC to AC and feeds it to household loads and the grid; a separate battery inverter then reconverts that AC back to DC to charge the battery. This retrofit-friendly wiring adds one extra conversion step compared with DC-coupled.<\/p>\n\n

Why it matters for home backup power<\/h2>\n\n

Most homes that already have solar come with a grid-tie solar inverter already in place. AC-coupling lets that existing equipment stay: a battery inverter is added alongside it, handling storage without requiring any changes to the solar side. The practical upside is a simpler retrofit; the trade-off is one additional energy conversion in the charging path.<\/p>\n\n

Every conversion step carries a small loss. In an AC-coupled setup, solar output passes through two conversions before reaching the battery: DC to AC at the solar inverter, then AC to DC at the battery inverter. In a DC-coupled<\/a> system, solar charges the battery directly on the DC bus, so only one conversion occurs. System-level round-trip efficiency, covering a full charge and discharge cycle, is about 90 percent for well-designed storage systems; AC-coupled systems sit toward the lower end of that range because of the extra step.(Source: Battery University BU-808<\/a>)<\/p>\n\n

AC-coupled in practice<\/h2>\n\n

Key numbers<\/h3>\n\n

For energy planning, expect about 85 percent of nameplate battery capacity as usable output: depth of discharge runs 80 to 95 percent, combined with one-way discharge and inverter efficiency of 90 to 95 percent. Backup duration is always load-dependent; the same battery covers a very different window powering minimal lighting than it does running high-draw appliances.<\/p>\n\n

AC-coupled vs DC-coupled<\/h3>\n\n

In a DC-coupled<\/a> system, solar output travels on the DC bus directly to a charge controller and into the battery, completing only one conversion on the way to storage. In an AC-coupled system, the solar inverter first converts DC to AC, and the battery inverter reconverts that AC back to DC for storage: one extra step. The practical balance: DC-coupled is the more efficient first choice for new installations; AC-coupled is the logical retrofit path when an existing solar inverter is already in service.<\/p>\n\n

How Genixgreen uses AC-coupled<\/h2>\n\n

Genixgreen has built LiFePO4 storage in its own factory since 2011 and ships to 100+ countries, with local stock in Odesa for delivery across Ukraine. Genixgreen battery systems support both AC-coupled and DC-coupled wiring, letting installers match the topology to an existing site or design a new installation for maximum efficiency. A hybrid inverter<\/a> can consolidate battery management and grid-tie functions in one unit, simplifying an AC-coupled retrofit.<\/p>\n\n

Related terms<\/h2>\n\n