These projects are expected to increase our generation portfolio by 50% to approximately 1.5 gigawatts by 2023, with a significant contribution coming from our energy storage business.
This next step-up in the size of our overall portfolio represents approximately 29% increase in our geothermal and solar capacity, and up to approximately 400% increase in our energy storage assets by the end of 2023.
As a result of our ambitious plan, we estimate that we will reach an annual run rate of $500 million in adjusted EBITDA toward the end of 2022, that we expect to continue to grow as we move forward with our plans in 2023 and onwards.
Total revenue for the full year 2020 were $705 million, down 5.5% from prior year.
In the quarter, revenues were down 6.8% over last year.
Full year 2020 consolidated gross profit was $276.3 million, resulting in a gross margin of 39.2%, 310 basis points higher than in 2019.
2020 ended with a net income attributable to the company stockholders of $85.5 million.
Diluted earnings per share for 2020 declined by 4% compared to last year, mainly impacted by a nonrecurring tax benefit recorded in 2019.
Excluding this tax benefit, diluted earnings per share increased by 13%.
For the quarter, diluted earnings per share increased 62.5% to $0.39 per share.
Adjusted EBITDA increased 9.3% to $420.2 million in 2020.
For the quarter, this was 7% increase compared to 2019.
In the product segment, revenue declined 22.5%, representing 21% of the total revenue in 2020.
Energy Storage segment revenues increased 7.6% year-over-year, to $15.8 million and represented 2% of our total revenue for the full year 2020.
In the fourth quarter, the electricity segment revenues grew 1.3% to $146 million while product segment revenue decreased 37.5% to $27 million in the fourth quarter of 2020.
Energy Storage segment revenue were $5.8 billion, increasing 36% year-over-year compared to $4.3 million in the fourth quarter of 2019.
Gross margin for the electricity segment for the full year expanded year-over-year to 44.6%.
For the fourth quarter, gross margin was 45.2%.
Electricity gross profit in the full year 2020 was positively impacted by $7.8 million in business interruption insurance payments compared to $9.3 million in 2019.
In the product segment, gross margin was 22.4% in the full year of 2020 compared to 23.6% in the prior year.
In the fourth quarter, we saw an increase in gross margin in the product segment of 160 basis points to 29.8%.
Energy Storage segment reported a positive gross margin of 11.1% for 2020 compared to a negative gross margin in 2019.
The electricity segment generated 92% of the total adjusted EBITDA in the full year of 2020, and electricity segment adjusted EBITDA increased 11% over last year.
The product segment generated 7% of the total adjusted EBITDA for the full year of 2020.
The Storage segment reported, for the first time, a full year positive adjusted EBITDA of $3.2 million, including $1.7 million in the fourth quarter.
For the full year 2020, we successfully raised approximately $760 million in the aggregate, including $340 million net proceeds from the issuance of common stock, [$290] million profit from the Bond Series four and approximately $130 million of proceeds from senior unsecured loan.
Our net debt as of December 31, 2020, was $920 million.
Cash and cash equivalents and restricted cash and cash equivalent as of December 31, 2020, was $537 million, compared to $153 million as of December 31, 2019.
The accompanying slide breaks down the use of cash for the 12 months and illustrate our ability to invest back in the business, service the debt and continue to return capital to our shareholders in the form of cash dividends, all from cash generated by our operation.
Our long-term and short-term debt as of December 31, 2020, was $1.46 billion, net of deferred financing costs.
The average cost of debt for the company is currently 4.7%.
On February 24, 2021, the company's Board of Directors declared, approved and authorized a payment of quarterly dividend of $0.12 per share pursued to the company dividend policy.
In addition, we expect to pay dividend of $0.12 per share in the next three quarters, representing a 9% increase over Q3 2020 dividend.
Power generation in our power plants declined by 3.1% compared to last year.
However, revenues of our electricity segment remain unchanged with higher average rate per megawatt hour of $89.6 compared to $86.6 million for last year.
We adjusted the generation capacity of our existing power plants based on their performance this year, as detailed on the slide, and the current portfolio stands at 932 megawatts compared to 914 megawatts last year.
This year, the main addition was 19 megawatts in Steamboat complex following the completion of the Steamboat enhancement.
As noted on slide 13, Puna reserved operations in November 2020, 2.5 years after the eruption of the Kilauea volcano, currently, at low output relative to its generating capacity before the eruption.
In November, Puna reached 10-megawatt generating capacity, and now it is offering at 13 megawatts.
On the insurance front, for the entire 2020, we collected $29.1 million insurance proceeds, the $7.8 million were recorded under cost of revenues and the balance in other operating income.
As discussed earlier, one of the impacts COVID had on our operations in Kenya relates to increased curtailment there by KPLC, which was the main driver to a reduction in revenue of approximately $6.5 million compared to prior year.
Also in Kenya, we had an important achievement, concluding all open tax audits with the Canadian tax authorities and reached a favorable settlement related to the 2019 Flex assessment originally totaling $200 million.
As of February 24, 2021, our product segment backlog was $33 million.
Inter-segment revenue increased more than 30% over 2019 and 130% over 2018.
In order to reduce our merchant risk and increase our contracted in 2021, the company signed a transaction for 80% of the volume at a fixed rate, exchanging the floating RF revenue -- for a fixed our revenue at the end of 2020.
Due to the inability to operate the facility during these times, we expect to record in Q1 financial results, up to approximately $11 million of nonrecurring loss associated with this hedge.
Our operating portfolio stands to date at over one gigawatt, comprising of 873 megawatts of geothermal, 53 megawatts offering, 7-megawatt of hybrid solar and 73 megawatts of energy storage.
We have a robust growth plan to increase by 2023, our total portfolio by almost 50%, with a significant contribution from the Energy Storage business, as detailed in the following slide.
From our previous estimate of approximately 170 megawatts by end of 2022 to between 250 and 270 megawatts by the end of 2023, representing a total increase of up to 29%.
In our rapidly growing energy storage portfolio, we are planning to enhance our growth and to increase our portfolio by up to approximately 400% -- between 200 megawatts to 300 megawatts by the end of 2023.
This represents a significant increase compared to our previous growth target of 80 to 175 megawatts, we set for 2021, 2022.
The next slide explains 14 projects under way that comprise the majority of our 2023 growth plans.
Moving to slide 24 and 25.
Our current pipeline presented in slide 25, which is updated frequently include 33 names, potential projects with a total potential capacity of over one gigawatt, which are in different stages of development.
As I mentioned earlier, we believe that we can develop from this potential pipeline between 200 to 300 megawatts by the end of '23, mainly in Texas, New Jersey and California.
To fund this growth, we have over $900 million of cash and available and restricted cash and lines of credits.
Our total expected capital expense for 2021 includes approximately $450 million for capital expenditure for construction of new projects of geothermal, solar and storage; enhancement to our existing geoterminal power plant at management release for construction; maintenance of capital expenditures, including our work at the Puna power plant; and enhancements to our production facilities as detailed in slide 32 in the appendix.
We expect total revenues between $640 million and $675 million, with electricity segment's revenue between $570 million and $580 million.
The electricity segment includes $32 million from the Puna power plant in Hawaii, assuming we are without plans, mainly close to full operations in mid-2021.
We expect product segments revenue between $50 million to $70 million.
Revenues for energy storage is expected to be between $20 million and $25 million.
We expect adjusted EBITDA to be between $400 million and $410 million.
We expect annual adjusted EBITDA attributable to minority interest to be approximately $32 million.
In addition, safe harbor provision for renewable energy developers to claim this tax credit was extended from five to 10 years.
Finally, a few days ago, the California Public Utility Commission, the CPUC issued a ruling requesting comment on a proposal for 1,000 megawatts, each of new geoterminal and long duration storage procurement between 2024 and 2026.
With the tailwind of this support, 2021 is going to be a significant buildup year, accelerating our growth in the storage and electricity with a goal to reach $500 million of annual run rate of adjusted EBITDA toward the end of 2022, that we expect to continue to grow as we move forward with our plans in 2023 and onwards.

Summary:
For the quarter, diluted earnings per share increased 62.5% to $0.39 per share.
We expect total revenues between $640 million and $675 million, with electricity segment's revenue between $570 million and $580 million.
We expect adjusted EBITDA to be between $400 million and $410 million.