On a US GAAP basis, for the fourth quarter of 2020, NOV reported revenues of $1.33 billion and a net loss of $347 million.
Consolidated revenue declined 4% sequentially and EBITDA fell to $17 million to 1.3% of sales in the fourth quarter.
The offshore rig count was down 37% from the fourth quarter of 2019 and the international rig count was down 40% year-over-year.
Although North America drilling has been improving since bottoming in August, it is still down 58% compared to the prior year which, by the way, wasn't exactly a robust oil and gas market either.
While we were pleased to see Rig Technologies' reported book to bill above 1 in the fourth quarter, that is the only book to bill NOV saw above 100% throughout 2020.
All three of our segments saw the majority of their revenue come from markets outside North America: 59% for Wellbore Technologies, 67% for Completion & Production Solutions, and 90% for Rig Technologies.
I'm proud that NOV was able to take out $700 million in fixed costs during 2020, but our poor fourth quarter results tell us that we must do more.
As we enter 2021, we've identified another $75 million in annual cost reductions that we are executing on right now, and we expect the target to grow as we progress through the year.
Fourth quarter cash flow from operations was $186 million and free cash flow was $133 million.
For the year, NOV generated cash flow from operations of $926 million and reduced our net debt by almost $700 million.
We completed the year with a very strong balance sheet, only $142 million in net debt, with our next major maturity not due until late 2009.
We remain committed to developing and delivering solutions that provide the world with abundant reliable safe energy, the oil and gas, that powers the world's global food supply chain, that powers 100% of its air travel and that helps lift humanity out of poverty.
NOV is proud to support this critical industry as we've done 159 years.
You may be surprised to learn that robust serious technical economic discussions about transitioning to new forms of energy actually began more than 40 years ago, following the Iranian hostage crisis and the second big oil shock of the 1970s.
In 2019, NOV invested in Keystone Tower Systems, a start-up that has developed a patented tapered spiral welding process that enables the automated production of wind tower sections, which can significantly decrease production times and reduce cost by 50% or more.
Keystone is currently completing construction of its first commercial line within NOV's Pampa, Texas facility and has an order for 100 tower sections from a major wind turbine manufacturer.
This has led the Global Wind Energy Council to forecast 26% compound annual growth rate for the offshore wind space through this decade.
Considering nearly 40% of the world's population, 2.5 billion people, live and consume power within 60 miles of the coast, this makes sense.
NOV has long been a leader in offshore wind construction vessels, on which we can sell as much as $80 million of equipment.
In fact, the majority of the world's 30 gigawatts of installed offshore power generation capacity was put in place with NOV-designed vessels and NOV-supplied equipment.
By year-end, I expect that our business in this area will have doubled to more than $200 million annually, and further growth prospects are excellent as the 9.6 gigawatts of offshore wind capacity to be installed in 2021 is forecast to more than double by 2025 to more than 21 gigawatts.
With revenue potential north of $25 million per vessel and dozens of vessels required to develop a single gigawatt project, NOV's total addressable market in this area is potentially in the billions.
We have a large and growing base of installed capacity in the fixed offshore wind installation vessel market, which we expect to exceed $200 million annually in revenue for us by year-end, along with an ongoing aftermarket opportunity.
Our Keystone team secured an order for 100 towers based on its proprietary technology that we are constructing in our plant in Texas.
NOV's consolidated revenue fell $57 million or 4% sequentially to $1.33 billion during the fourth quarter of 2020.
Our shorter cycle businesses capitalized on improving drilling activity levels in the US to drive 4% revenue growth in North America, despite very light demand for capital equipment sales.
International revenue declined 7%, reflecting the different trajectories of rig activity between the eastern and western hemispheres during the quarter.
EBITDA for the fourth quarter was $17 million, or 1.3% of sales.
While we exceeded our $700 million cost-out initiative target in the third quarter of 2020, our efforts to right-size and improve the efficiencies of the organization continued during the fourth quarter.
As Clay mentioned, we've identified and are executing on $75 million in additional cost savings initiatives that we expect to complete by year-end 2021, and we expect our target will grow.
During the fourth quarter, we generated $186 million in cash flow from operations and $133 million in free cash flow.
We ended the year with approximately $1.69 billion in cash and $1.83 billion in gross debt, resulting in a net debt balance of only $142 million, down $676 million year-over-year.
For the full year, cash flow from operations was $926 million and free cash flow totaled $700 million.
The organization's focus on reducing costs, improving capital efficiency and optimizing cash flow allowed us to reduce net debt by 83% during 2020, further improving what was already a rock-solid balance sheet.
For 2021, we expect to report capital expenditures of approximately $215 million with $82 million of that amount related to completing our rig manufacturing facility in Saudi Arabia.
Factoring in the 30% that will be funded by our JV partner, net capex will total $190 million.
Our Wellbore Technologies segment generated revenue of $373 million in the fourth quarter, an increase of $12 million or 3% sequentially.
Despite the top line growth, EBITDA fell to $12 million or 3.2% of sales, primarily due to an unfavorable shift in product mix and COVID-19-induced shipping cost overruns and delays.
Our Grant Prideco drill pipe business realized a 24% sequential decline in revenue with very high decremental margins.
Lower volumes, a significant decrease in proportion of higher-margin large-diameter pipe and extra costs associated with shipping delays in Asia more than offset the unit's cost reduction efforts, which included reducing its workforce by approximately 25% during the first week of the quarter.
Orders improved 84% off the all-time low level realized in the third quarter but were less than half the level achieved in Q4 of 2019.
Our Tuboscope pipe coating and inspection business realized a 7% sequential improvement in revenue, led by a 28% increase in our activity from the OCTG market.
Our downhole tools business saw a 5% sequential increase in revenue, driven by the improving North American rig count, which was partially offset by lower activity in the eastern hemisphere.
During the fourth quarter, we saw a significant increase in the number of runs completed by our SelectShift downhole adjustable motor, which now incorporates our latest ERT power section, allowing for up to 1,000 horsepower to be delivered to the drill bit, further enhancing the motor's ability to drill single run horizontal wells.
A major national oil company in the Middle East recently completed a 12.25 inch directional section using our Agitator tool, resulting in a 38% improvement in the rate of penetration relative to nearby offsets.
Our Wellsite Services business generated 17% sequential growth in revenue during the fourth quarter on the meaningful improvement of drilling activity levels across the western hemisphere.
We also expect an improved mix in product sales and cost controls to result in EBITDA margins expanding approximately 200 basis points to 400 basis points.
Our Completion & Production Solutions segment generated $546 million in revenue during the fourth quarter, a decrease of $55 million or 9% sequentially.
While orders did improve 27% sequentially to $15 million, the resurgence of COVID-19 through the quarter reduced customer conviction, slowed order intake and led to the segment's fourth straight quarter with a book to bill below 1.
Further deterioration of the segment's backlog created additional absorption challenges and a less favorable product mix, resulting in an EBITDA that declined $35 million to $28 million or 5.1% of sales.
Our subsea flexible pipe business saw revenue decline of 11% sequentially with high decremental margins.
Our Process and Flow Technologies business experienced a 4% sequential revenue decline, primarily due to deterioration in the backlog of our APL turret loading offerings, which is facing similar challenges to what I just described in our subsea business.
Or fiberglass systems business saw revenue decline approximately 19% sequentially due to customers that continue to defer deliveries for offshore scrubbers and limited demand from midstream infrastructure, which has depleted our backlog for large diameter, high pressure pipe.
Or Intervention and Stimulation Equipment business realized a 9% sequential decline in the four quarter.
In Q4, we realized our second quarter in a row of improving demand for replacement coiled tubing strings, and we are engaging in a steadily increasing number of conversations with customers looking to refurbish or upgrade pressure pumping equipment from Tier 2 to Tier 4 motors with dual fuel capabilities.
We recently received an order from a customer to refurbish 35 pressure pumping units.
For the first quarter of 2021, we anticipate revenue from our Completion & Production Solutions segment will decline 6% to 10% sequentially with decremental margins in the mid-30% range.
Our Rig Technologies segment generated revenues of $437 million in the fourth quarter, a decrease of $12 million or 3% sequentially.
Revenue from capital equipment sales declined 7%, partially offset by an increase in aftermarket services.
EBITDA declined to $19 million or 4.3% of sales.
Additionally, the segment incurred extra expenses associated with the logistical challenges of moving 200 service technicians and associated equipment across numerous international borders during a second round of pandemic-related restrictions.
Orders for the segment increased $133 million sequentially off the all-time low realized in the third quarter to $190 million, yielding a book to bill of 105%.
And in Q4, we received an order from a customer in the Middle East for two 1,000 horsepower land rigs, fully equipped with automated pipe handling systems, NOVOS drilling automation and our Maestro Power Management system.

Summary:
On a US GAAP basis, for the fourth quarter of 2020, NOV reported revenues of $1.33 billion and a net loss of $347 million.
NOV's consolidated revenue fell $57 million or 4% sequentially to $1.33 billion during the fourth quarter of 2020.
We ended the year with approximately $1.69 billion in cash and $1.83 billion in gross debt, resulting in a net debt balance of only $142 million, down $676 million year-over-year.
Factoring in the 30% that will be funded by our JV partner, net capex will total $190 million.
Our Completion & Production Solutions segment generated $546 million in revenue during the fourth quarter, a decrease of $55 million or 9% sequentially.
While orders did improve 27% sequentially to $15 million, the resurgence of COVID-19 through the quarter reduced customer conviction, slowed order intake and led to the segment's fourth straight quarter with a book to bill below 1.
Orders for the segment increased $133 million sequentially off the all-time low realized in the third quarter to $190 million, yielding a book to bill of 105%.