BTU Int'l (BTUI) and Astronics (ATRO)

The top-performing Zacks #1 Rank company on Monday was BTU International, Inc. (BTUI - Snapshot Report), which gained a little more than 10% to start off the week.

The vast majority of Zacks #1 Rank stocks today finished higher, which was to be expected on a day when the Dow reclaimed 12,000. However, BTUI was the only company to finish the session with a double-digit improvement.

We can count BTU Int'l as the latest in a long line of alternative energy-related stocks that have been spending time on the Zacks #1 Rank List. 'Spending time' is actually an understatement; several of these companies have been putting together strong enough performances to stand out in a portfolio of standouts.

BTUI is no exception. In its fourth-quarter report, which was announced earlier this month, the company stated that its alternative energy business exceeded its electronics assembly business as the primary contributor of net sales for the first time. Alternative energy contributed 60% of sales in the quarter.

As far as that quarter is concerned, BTU Int'l reported net sales of $27.4 million, which was 127% better than a year earlier. Meanwhile, earnings per share of 24 cents topped the Zacks Consensus Estimate by an even 100%. This marked the fourth straight quarter with a positive earnings surprise; in fact, the last 3 quarters have beaten in the triple digits.

There aren't many analysts covering BTUI right now, but the trajectory of earnings estimates is nonetheless to the upside (see graph above).

The Zacks Consensus Estimate for 2011 is 61 cents per share, which is up 27% in the past 30 days. Meanwhile, the Zacks Consensus Estimate for 2012 suggests year-over-year profit growth of more than 44% to 88 cents per share. That guidance has advanced 6% in the past month.

BTU International is a market-leading, global supplier of advanced thermal processing equipment and processes to the alternative energy and electronics manufacturing markets. The company’s equipment is used in solar cell, nuclear fuel and fuel cell manufacturing as well as in the production of printed circuit board assemblies and semiconductor packaging.

BTUI is part of the electronics – manufacturing machinery industry. There is only 1 other company from this space on today's Zacks #1 Rank List: GT Solar International, Inc. (SOLR).

The only company to come within 1% of BTUI on today's list was Astronics Corporation (ATRO - Snapshot Report), which was up nearly 9.2% today.

ATRO is a leader in advanced, high-performing lighting, electrical power and automated test systems for the global aerospace and defense industries. The company and its subsidiaries have a reputation for high-quality designs, exceptional responsiveness, strong brand recognition and best-in-class manufacturing practices.

As you can probably guess from the company's name, Astronics is part of the aerospace/defense equipment industry. There is only 1 other name from that space on today's Zacks #1 Rank: Esterline Technologies Corporation (ESL - Snapshot Report).

In its fourth-quarter report from last month, ATRO announced earnings per share of 39 cents, which were ahead of the Zacks Consensus Estimate by more than 18%. This marked the company's sixth straight quarter with a positive earnings surprise.

Sales were up 13.7% to $51.8 million from $45.6 million last year. Aerospace sales made up 90% of consolidated sales. It increased nearly 30% while sales for Test Systems declined.

ATRO said it expects another solid year in 2011, and sees sales between $205 million and $215 million.

The past 2 months have seen solid improvements in earnings estimates.

The Zacks Consensus Estimate for 2011 is at $1.47 per share, which is up nearly 6% in 60 days. Meanwhile, the Zacks Consensus Estimate for 2012 is up 9% in that time to its current reading of $1.80 per share, which also suggests year-over-year growth of as much as 22.4.

Read the full analyst report on BTUI

Read the full analyst report on ESL

Read the full analyst report on ATRO

Read the full analyst report on SOLR