What was the adjusted EBITDA for the fourth quarter of 2019 
diary. And Geoverse has begun deploying into several verticals and is also partnering with multiple players interested in taking advantage of its network layer solution. What we see is the next stage of industry development of in-building and enterprise solutions is still early in its development, but we and many other participants expect things to move fairly quickly in 2020 and certainly 2021 with the advancement of the CBRS and 5G technology ecosystems. And as building owners and occupants realize, there is a much more powerful, secure and reliable solution than Wi-Fi available.
In renewable energy, while the revenue was relatively immaterial on a consolidated basis, the team was busy pursuing two large builds for top-tier corporate off-takers, and we hope these activities lead to a larger contribution as we get deeper into 2020. And as noted in our press release, we have invested approximately $32 million over the past three years and four early stage companies with telecom technology or services business models. In rough order of investment size, these include an international communications tower and neutral host company, two wireless technology companies and a developer of a new satellite antenna technology. While this company features still in relatively early stages of development, we are optimistic about creating shareholder value here, both through financial returns and through the contribution, in some cases, of technologies or solutions that leads to other business success at ATN.
We've also made controlling investments in several other businesses, including a private LTE in-building company and managed and cloud services business and long-haul fiber initiatives. The managed services business, Fireminds, is growing nicely for a young company and is contributing to the product set of both our international and U.S. telecom businesses. The fiber business is in protracted discussions with customers and what unsurprisingly is proving to be a long sales cycle business.
The in-building company, Geoverse, which I just discussed, has developed a strong solution and positive momentum. So to summarize for the quarter, I think the key takeaways are, while operating income and net income were negatively impacted by some impairments and other losses related to certain of our minority and overseas investments, our largest businesses performed well. And we were able to continue the positive momentum in our telecom segments through year end, and our visibility is quite a bit better today than it was a year ago. We like where these businesses are right now, and we expect continued positive comparisons as we move into 2020.
And with that, I'll hand it back to you, Jeff.
Justin Benincasa -- Chief Financial Officer
Great. Thank you, Michael. Just beginning with some of the relevant financial data. For the fourth quarter, total consolidated reported revenues were $112.1 million, up 4% from last year's reported total of $107.8 million.
Adjusting for the sale of the U.S. solar portfolio completed in late 2018, revenue increased 7% from last year. Throughout the year, we consistently reported steady revenue growth and improving profits from the international telecom segment. The U.S.
telecom segment also showed significant improvement this quarter over last year, and its revenue and EBITDA performance in the second half of the year was up 27% and 140%, respectively, from the first half of 2019. This reflects the benefits from the CAF II Federal Support Award that we won in 2018 and increased wholesale revenue as part of the FirstNet transaction. Consolidated adjusted EBITDA for the quarter was $28.5 million, an increase of 22% over 2018 adjusted EBITDA of $23.4 million. Adjusting for the sale of the U.S.
solar portfolio, adjusted EBITDA increased 39% year on year. Looking at the segments and starting with the international telecom. Starting with international telecom, fourth-quarter revenues were up 6% to $83.1 million from $78 million last year, and adjusted EBITDA increased 29% to $26.6 million from $20.6 million. As Michael ment
diary. And Geoverse has begun deploying into several verticals and is also partnering with multiple players interested in taking advantage of its network layer solution. What we see is the next stage of industry development of in-building and enterprise solutions is still early in its development, but we and many other participants expect things to move fairly quickly in 2020 and certainly 2021 with the advancement of the CBRS and 5G technology ecosystems. And as building owners and occupants realize, there is a much more powerful, secure and reliable solution than Wi-Fi available.
In renewable energy, while the revenue was relatively immaterial on a consolidated basis, the team was busy pursuing two large builds for top-tier corporate off-takers, and we hope these activities lead to a larger contribution as we get deeper into 2020. And as noted in our press release, we have invested approximately $32 million over the past three years and four early stage companies with telecom technology or services business models. In rough order of investment size, these include an international communications tower and neutral host company, two wireless technology companies and a developer of a new satellite antenna technology. While this company features still in relatively early stages of development, we are optimistic about creating shareholder value here, both through financial returns and through the contribution, in some cases, of technologies or solutions that leads to other business success at ATN.
We've also made controlling investments in several other businesses, including a private LTE in-building company and managed and cloud services business and long-haul fiber initiatives. The managed services business, Fireminds, is growing nicely for a young company and is contributing to the product set of both our international and U.S. telecom businesses. The fiber business is in protracted discussions with customers and what unsurprisingly is proving to be a long sales cycle business.
The in-building company, Geoverse, which I just discussed, has developed a strong solution and positive momentum. So to summarize for the quarter, I think the key takeaways are, while operating income and net income were negatively impacted by some impairments and other losses related to certain of our minority and overseas investments, our largest businesses performed well. And we were able to continue the positive momentum in our telecom segments through year end, and our visibility is quite a bit better today than it was a year ago. We like where these businesses are right now, and we expect continued positive comparisons as we move into 2020.
And with that, I'll hand it back to you, Jeff.
 Justin Benincasa -- Chief Financial Officer
Great. Thank you, Michael. Just beginning with some of the relevant financial data. For the fourth quarter, total consolidated reported revenues were $112.1 million, up 4% from last year's reported total of $107.8 million.
Adjusting for the sale of the U.S. solar portfolio completed in late 2018, revenue increased 7% from last year. Throughout the year, we consistently reported steady revenue growth and improving profits from the international telecom segment. The U.S.
telecom segment also showed significant improvement this quarter over last year, and its revenue and EBITDA performance in the second half of the year was up 27% and 140%, respectively, from the first half of 2019. This reflects the benefits from the CAF II Federal Support Award that we won in 2018 and increased wholesale revenue as part of the FirstNet transaction. Consolidated adjusted EBITDA for the quarter was $28.5 million, an increase of 22% over 2018 adjusted EBITDA of $23.4 million. Adjusting for the sale of the U.S.
solar portfolio, adjusted EBITDA increased 39% year on year. Looking at the segments and starting with the international telecom. Starting with international telecom, fourth-quarter revenues were up 6% to $83.1 million from $78 million last year, and adjusted EBITDA increased 29% to $26.6 million from $20.6 million. As Michael ment