EcoSeed

A California-based company which makes electronics that can improve how solar panels convert sunlight into energy by as much as 20 percent raised $18 million in its fourth financing round as it expands manufacturing and international sales.

Tigo Energy makes power optimizers about the size of a computer modem which are installed on the back of each solar panel in an array. A single device, called a maximizer management unit, calculates the optimal performance of the solar array and "tunes" each panel to achieve it.

Proceeds from the series D could support Tigo's current partnerships with companies that have agreed to install its device into their solar products.

In October, the company announced that Trina Solar, the fourth largest solar panel company worldwide, Hanwha Solar and Upsolar will offer Tigo-optimized solar panels, broadening the company's reach in the market more quickly. The system has versions for utility, commercial and residential solar installations.

The current round brought the company's total venture capital funding to just over $50 million. The round was led by Bessemer Venture Partners and joined by all existing investors including Inventec Appliances, Clal, Matrix Partners and OVP Venture Partners.

"Tigo Energy has a winning solution that has attracted many of the world's largest PV suppliers," said Lucinda Stewart, managing director at OVP. "Tigo Energy's technology helps customers of solar installations earn the most out of their investment, and we're pleased to continue to support the company's strong growth."

Power optimizer

In a typical solar array, panels are connected together in a series to form groups wired to the inverter - converting direct current to usable alternating current. Though this set-up helps in making installation easier, the disadvantage is that weak-performing panels can drag down the power production of the array.

Micro-inverter systems have been introduced as an alternative to central inverters by installing a small, efficient inverter on each panel. These devices also can optimize solar panels, but not as closely as power optimizers, according to Tigo.

The company said the Energy Maximizer uses algorithms and software based on real-time conditions to accurately compute the adjustments in each panel. Micro-inverters are said to base calculations on averages. (Oliver M. Bayani)