PETALUMA -- Enphase Energy, Inc. (Nasdaq: ENPH) on Tuesday reported net revenue increased nearly 8 percent last year and 16 percent in the fourth quarter, while net losses narrowed for the year and quarter, as shipments of solar panel electricity microinverters reached a record level.

Net revenue was $67.1 million for the quarter and $232.8 million for the calendar year.

Net loss for the year totaled $25.9 million, or 62 cents a share, down from $38.2 million a year before. The loss for the quarter was $2.81 million, or 7 cents a share, down from $7.74 million, or 19 cents a share, a year before.

"We ended 2013 with a breakthrough fourth quarter," said Paul Nahi, chief executive officer, in a statement. "We posted the highest revenue in our company's history, shipping over 100 megawatts for the first time in any quarter, while our record gross margin marks the first time we have exceeded 30 percent in any quarter. Combined with our ongoing focus on expense management, we were able to post a non-GAAP operating profit for the first time in Enphase's history. We also continue to drive working capital improvements, resulting in strong cash generation during the quarter."

Losses from operations was $1.61 million in the fourth quarter and $22.16 million for the year, down from $6.18 million and $31.16 million, respectively, a year before.

On a pro forma basis, Enphase had its first profitable quarter, reporting operations income of $0.4 million, up from an operating loss of $4.2 million a year before. Pro forma losses were $18.0 million, or 43 cents a share, for the year and $700,000, or 2 cents a share, for the quarter.

Founded in March 2006 and making its first commercial shipment in mid-2008, Enphase said it shipped 485,000 microinverters in the fourth quarter, equivalent to 107 megawatts of installed energy system production capacity, the first quarter passing 100 megawatts in shipments, according to the company. Those shipments were up 14 percent from the third quarter and 30 percent from a year before.

For the full calendar year, shipments totaled 1.6 million microinverters, equivalent to 355 megawatts. These devices convert direct current from the panel to alternating current like what's supplied by the local utility. Mounting the units on each panel, instead of the conventional approach of a collective inverter for an array of panels, is designed to make maintenance of the panels safer and energy production more efficient.

First-quarter revenues are forecast to be $54 million to $57 million, gross margin of 30 percent to 33 percent and operating expenses up 5 percent to 8 percent from the first quarter of last year, according to said Kris Sennesael, chief financial officer.Shares of Enphase were $7.58 each at the close of trading Tuesday, up 28 cents, or 3.84 percent, from the closing price Friday.