management evaluates the performance of our product segment based on the timely delivery of our products , performance quality of our products , revenues and costs actually incurred to complete customer orders compared to the costs originally budgeted for such orders . 102 trends and uncertainties trends , factors and uncertainties may impact our operations and financial condition , including many that we do not or can not foresee . however , we believe that our results of operations and financial condition for the foreseeable future will be primarily affected by the following trends , factors and uncertainties that are from time to time also subject to market cycles : ● there has been increased demand for energy generated from geothermal and other renewable resources in the u.s. as costs for electricity generated from renewable resources have become more competitive . much of this is attributable to legislative and regulatory requirements and incentives , such as state rps and federal tax credits such as ptcs or itcs ( which are discussed in more detail in the section entitled “ government grants and tax benefits ” below ) . we believe that future demand for energy generated from geothermal and other renewable resources in the u.s. will be driven primarily by further commitment and implementation of state rps and greenhouse gas initiatives . ● we accelerated our efforts to expand business development activities in developing countries where geothermal is considered a local resource that can provide a stable and cost effective solution to increase access to power . we expect that a variety of local governmental initiatives will create new opportunities for the development of new projects with the potential to realize higher returns on our equity as well as to create additional markets for our products . these initiatives include the award of long-term contracts to independent power generators , the creation of competitive wholesale markets for selling and trading energy , capacity and related energy products and the adoption of programs designed to encourage “ clean ” renewable and sustainable energy sources . ● we expect to continue to generate the majority of our revenues from our electricity segment through the sale of electricity from our power plants . all of our current revenues from the sale of electricity are derived from payments under long-term ppas related to fully-contracted power plants . as a result of the operational improvements and technological advancements that were implemented and that we plan to continue to implement in our operating portfolio , including capacity additions , geographical expansion and re-contracting of existing power plants , we expect that the electricity segment contribution to our operating income will increase further in the future . due to the increasing contribution of our electricity segment to our operating income compared to the contribution of our product segment , and due to the nature of the product segment where revenues are less stable , we are targeting to increase future revenues from our electricity segment in order to increase revenues , profitability and stability . we also intend to continue to pursue opportunities as they arise in our recovered energy business , in the solar pv sector , in the energy storage market and in other forms of clean energy . in addition , pursuant to our strategic plan , we acquired our viridity business which operates in the energy storage , demand response and energy management markets and generates revenues derived primarily from software license fees and the provision of services . we are also pursuing ppas with enterprises that will increase our potential customer base . ● we have adopted a strategic plan for the growth of our company , in terms of geographic scope , customer base , and technology platforms covered by our product and service offerings , with a focus on increasing net income from operations . under this plan , we will continue to focus on organic growth and increasing operational efficiency of our existing business lines . in addition , we are actively pursuing domestic and international acquisition opportunities , both within our existing business lines and the solar power generation and energy storage businesses , all of which are targeted as part of the plan . for example , we recently acquired our interest in the bouillante geothermal power plant in guadeloupe and signed a definitive agreement to acquire u.s. geothermal inc. ( nyse american : htm ) , a renewable energy company focused on the development , production and sale of electricity from geothermal energy . we also completed the acquisition of our viridity business during fiscal year 2017. as part of our services offering expansion through our viridity business , we have developed our battery storage as a service ( “ bsaas ” ) strategy to provide comprehensive holistic solutions for energy storage , demand response , energy management through nimble and flexible business models , technology and product solutions . we plan to develop , build , own and operate energy storage facilities and provide related services in diversified markets . we will face a number of challenges and uncertainties in implementing this plan , including integration of recently acquired assets as well as potential new acquisitions , and we may revise elements of the plan in response to market conditions or other factors as we move forward with the plan . 103 ● in the electricity segment , we expect intense domestic competition from the solar and wind power generation industries to continue and increase . while we believe the expected demand for renewable energy will be large enough to accommodate increased competition , any such increase in competition , including increasing amounts of renewable energy under contract as well as any further decline in natural gas prices attributable to increased production may contribute to a reduction in electricity prices . story_separator_special_tag royalties constituted approximately 4.1 % and 3.9 % of electricity segment revenues for the years ended december 31 , 2017 and december 31 , 2016 , respectively . product segment the principal cost of revenues attributable to our product segment includes materials , salaries and related employee benefits , expenses related to subcontracting activities , and transportation expenses . sales commissions to sales representatives are included in selling and marketing expenses . some of the principal expenses attributable to our product segment , such as a portion of the costs related to labor , utilities and other support services are fixed , while others , such as materials , construction , transportation and sales commissions , are variable and may fluctuate significantly , depending on market conditions . as a result , the cost of revenues attributable to our product segment , expressed as a percentage of total revenues , fluctuates . another reason for such fluctuation is that in responding to bids for our products , we price our products and services in relation to existing competition and other prevailing market conditions , which may vary substantially from order to order . cash and cash equivalents our cash and cash equivalents , as of december 31 , 2017 , decreased to $ 47.8 million from $ 230.2 million as of december 31 , 2016. this decrease is principally attributable to : ( i ) our use of $ 259.2 million to fund capital expenditures ; ( ii ) repayment of $ 66.2 million of long-term debt ; ( iii ) an investment in an unconsolidated company of $ 46.3 million ; ( iv ) $ 35.3 million net cash paid for the acquisition of our viridity business ; ( v ) $ 21.3 million paid to noncontrolling interest ; ( vi ) payment of a $ 20.5 million dividend ; ( vii ) a net change in restricted cash and cash equivalents of $ 14.6 million ; and ( viii ) $ 14.3 million of cash paid to prepay our ofc senior secured notes . this decrease was partially offset by : ( i ) $ 245.6 million derived from operating activities during the year ended december 31 , 2017 ; and ( ii ) net proceeds of $ 51.5 million from our revolving credit lines with commercial banks . as described below in “ liquidity and capital resources ” , our corporate borrowing capacity under committed lines of credit with different commercial banks as of december 31 , 2017 was $ 468.0 million , of which we have utilized $ 330.2 million as of december 31 , 2017. critical accounting estimates and assumptions our significant accounting policies are more fully described in note 1 to our consolidated financial statements set forth in item 8 of this annual report . however , certain of our accounting policies are particularly important to an understanding of our financial position and results of operations . in applying these critical accounting estimates and assumptions , our management uses its judgment to determine the appropriate assumptions to be used in making certain estimates . such estimates are based on management 's historical experience , the terms of existing contracts , management 's observance of trends in the geothermal industry , information provided by our customers and information available to management from other outside sources , as appropriate . such estimates are subject to an inherent degree of uncertainty and , as a result , actual results could differ from our estimates . our critical accounting policies include : revenues and cost of revenues . revenues related to the sale of electricity from our geothermal and reg power plants and capacity payments paid in connection with such sales ( electricity revenues ) are recorded based upon output delivered and capacity provided by such power plants at rates specified pursuant to the relevant ppas . revenues related to ppas accounted for as operating leases with minimum lease rentals which vary over time are generally recognized on a straight-line basis over the term of the ppa . ppas with contingent rentals are recognized when earned . 108 revenues generated from the construction of geothermal and recovered energy-based power plant equipment and other equipment on behalf of third parties ( product revenues ) are recognized using the percentage of completion method , which requires estimates of future costs over the full term of product delivery . such cost estimates are made by management based on prior operations and specific project characteristics and designs . if management 's estimates of total estimated costs with respect to our product segment are inaccurate , then the percentage of completion is inaccurate resulting in an over- or under-estimate of gross margins . as a result , we review and update our cost estimates on significant contracts on a quarterly basis , and at least on an annual basis for all others , or when circumstances change and warrant a modification to a previous estimate . changes in job performance , job conditions , and estimated profitability , including those arising from the application of penalty provisions in relevant contracts and final contract settlements , may result in revisions to costs and revenues and are recognized in the period in which the revisions are determined . provisions for estimated losses relating to contracts are made in the period in which such losses are determined . revenues generated from engineering and operating services and sales of products and parts are recorded once the service is provided or product delivery is made , as applicable . property , plant and equipment . we capitalize all costs associated with the acquisition , development and construction of power plant facilities . major improvements are capitalized and repairs and maintenance ( including major maintenance ) costs are expensed . we estimate the useful life of our power plants to range between 25 and 30 years . such estimates are made by management based on factors such as prior

liquidity impact of uncertain tax positions as discussed in note 19 to our consolidated financial statements set forth in item 8 of this annual report , we have a liability associated with unrecognized tax benefits and related interest and penalties in the amount of approximately $ 8.9 million as of december 31 , 2017. this liability is included in long-term liabilities in our consolidated balance sheet , because we generally do not anticipate that settlement of the liability will require payment of cash within the next twelve months . we are not able to reasonably estimate when we will make any cash payments required to settle this liability . dividend the following are the dividends declared by us during the past two years : replace_table_token_13_th historical cash flows the following table sets forth the components of our cash flows for the relevant periods indicated : replace_table_token_14_th for the year ended december 31 , 2017 net cash provided by operating activities for the year ended december 31 , 2017 was $ 245.6 million , compared to $ 159.3 million for the year ended december 31 , 2016. this increase of $ 86.3 million resulted primarily from ( i ) an increase in receivables of $ 24.0 million in the year ended december 31 , 2017 , compared to $ 33.3 million in the year ended december 31 , 2016 , as a result of timing of collections from our customers ; and ( ii ) a decrease in billing in excess of costs and estimated earnings on uncompleted contracts , net of $ 0.1 million in our product segment in the year ended december 31 , 2017 , compared to $ 29.3 million in the year ended december 31 , 2016 , as a result of timing in billing of our customers ; and ( iii ) an increase in accounts payable and accrued expenses of $ 51.6 million in the year ended december 31 , 2017 , compared to a decrease of $ 1.4 million in the year ended december 31 , 2016 , as a result of timing of payments to our suppliers .


 Write a concise suspicious activity report of the following text delimited by triple backquotes. Return your response as a formal report which covers the key points highlighting the location,dates,entity names and account holder information in chronological order of the text.
     ```liquidity impact of uncertain tax positions as discussed in note 19 to our consolidated financial statements set forth in item 8 of this annual report , we have a liability associated with unrecognized tax benefits and related interest and penalties in the amount of approximately $ 8.9 million as of december 31 , 2017. this liability is included in long-term liabilities in our consolidated balance sheet , because we generally do not anticipate that settlement of the liability will require payment of cash within the next twelve months . we are not able to reasonably estimate when we will make any cash payments required to settle this liability . dividend the following are the dividends declared by us during the past two years : replace_table_token_13_th historical cash flows the following table sets forth the components of our cash flows for the relevant periods indicated : replace_table_token_14_th for the year ended december 31 , 2017 net cash provided by operating activities for the year ended december 31 , 2017 was $ 245.6 million , compared to $ 159.3 million for the year ended december 31 , 2016. this increase of $ 86.3 million resulted primarily from ( i ) an increase in receivables of $ 24.0 million in the year ended december 31 , 2017 , compared to $ 33.3 million in the year ended december 31 , 2016 , as a result of timing of collections from our customers ; and ( ii ) a decrease in billing in excess of costs and estimated earnings on uncompleted contracts , net of $ 0.1 million in our product segment in the year ended december 31 , 2017 , compared to $ 29.3 million in the year ended december 31 , 2016 , as a result of timing in billing of our customers ; and ( iii ) an increase in accounts payable and accrued expenses of $ 51.6 million in the year ended december 31 , 2017 , compared to a decrease of $ 1.4 million in the year ended december 31 , 2016 , as a result of timing of payments to our suppliers .
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 Suspicious Activity Report : management evaluates the performance of our product segment based on the timely delivery of our products , performance quality of our products , revenues and costs actually incurred to complete customer orders compared to the costs originally budgeted for such orders . 102 trends and uncertainties trends , factors and uncertainties may impact our operations and financial condition , including many that we do not or can not foresee . however , we believe that our results of operations and financial condition for the foreseeable future will be primarily affected by the following trends , factors and uncertainties that are from time to time also subject to market cycles : ● there has been increased demand for energy generated from geothermal and other renewable resources in the u.s. as costs for electricity generated from renewable resources have become more competitive . much of this is attributable to legislative and regulatory requirements and incentives , such as state rps and federal tax credits such as ptcs or itcs ( which are discussed in more detail in the section entitled “ government grants and tax benefits ” below ) . we believe that future demand for energy generated from geothermal and other renewable resources in the u.s. will be driven primarily by further commitment and implementation of state rps and greenhouse gas initiatives . ● we accelerated our efforts to expand business development activities in developing countries where geothermal is considered a local resource that can provide a stable and cost effective solution to increase access to power . we expect that a variety of local governmental initiatives will create new opportunities for the development of new projects with the potential to realize higher returns on our equity as well as to create additional markets for our products . these initiatives include the award of long-term contracts to independent power generators , the creation of competitive wholesale markets for selling and trading energy , capacity and related energy products and the adoption of programs designed to encourage “ clean ” renewable and sustainable energy sources . ● we expect to continue to generate the majority of our revenues from our electricity segment through the sale of electricity from our power plants . all of our current revenues from the sale of electricity are derived from payments under long-term ppas related to fully-contracted power plants . as a result of the operational improvements and technological advancements that were implemented and that we plan to continue to implement in our operating portfolio , including capacity additions , geographical expansion and re-contracting of existing power plants , we expect that the electricity segment contribution to our operating income will increase further in the future . due to the increasing contribution of our electricity segment to our operating income compared to the contribution of our product segment , and due to the nature of the product segment where revenues are less stable , we are targeting to increase future revenues from our electricity segment in order to increase revenues , profitability and stability . we also intend to continue to pursue opportunities as they arise in our recovered energy business , in the solar pv sector , in the energy storage market and in other forms of clean energy . in addition , pursuant to our strategic plan , we acquired our viridity business which operates in the energy storage , demand response and energy management markets and generates revenues derived primarily from software license fees and the provision of services . we are also pursuing ppas with enterprises that will increase our potential customer base . ● we have adopted a strategic plan for the growth of our company , in terms of geographic scope , customer base , and technology platforms covered by our product and service offerings , with a focus on increasing net income from operations . under this plan , we will continue to focus on organic growth and increasing operational efficiency of our existing business lines . in addition , we are actively pursuing domestic and international acquisition opportunities , both within our existing business lines and the solar power generation and energy storage businesses , all of which are targeted as part of the plan . for example , we recently acquired our interest in the bouillante geothermal power plant in guadeloupe and signed a definitive agreement to acquire u.s. geothermal inc. ( nyse american : htm ) , a renewable energy company focused on the development , production and sale of electricity from geothermal energy . we also completed the acquisition of our viridity business during fiscal year 2017. as part of our services offering expansion through our viridity business , we have developed our battery storage as a service ( “ bsaas ” ) strategy to provide comprehensive holistic solutions for energy storage , demand response , energy management through nimble and flexible business models , technology and product solutions . we plan to develop , build , own and operate energy storage facilities and provide related services in diversified markets . we will face a number of challenges and uncertainties in implementing this plan , including integration of recently acquired assets as well as potential new acquisitions , and we may revise elements of the plan in response to market conditions or other factors as we move forward with the plan . 103 ● in the electricity segment , we expect intense domestic competition from the solar and wind power generation industries to continue and increase . while we believe the expected demand for renewable energy will be large enough to accommodate increased competition , any such increase in competition , including increasing amounts of renewable energy under contract as well as any further decline in natural gas prices attributable to increased production may contribute to a reduction in electricity prices . story_separator_special_tag royalties constituted approximately 4.1 % and 3.9 % of electricity segment revenues for the years ended december 31 , 2017 and december 31 , 2016 , respectively . product segment the principal cost of revenues attributable to our product segment includes materials , salaries and related employee benefits , expenses related to subcontracting activities , and transportation expenses . sales commissions to sales representatives are included in selling and marketing expenses . some of the principal expenses attributable to our product segment , such as a portion of the costs related to labor , utilities and other support services are fixed , while others , such as materials , construction , transportation and sales commissions , are variable and may fluctuate significantly , depending on market conditions . as a result , the cost of revenues attributable to our product segment , expressed as a percentage of total revenues , fluctuates . another reason for such fluctuation is that in responding to bids for our products , we price our products and services in relation to existing competition and other prevailing market conditions , which may vary substantially from order to order . cash and cash equivalents our cash and cash equivalents , as of december 31 , 2017 , decreased to $ 47.8 million from $ 230.2 million as of december 31 , 2016. this decrease is principally attributable to : ( i ) our use of $ 259.2 million to fund capital expenditures ; ( ii ) repayment of $ 66.2 million of long-term debt ; ( iii ) an investment in an unconsolidated company of $ 46.3 million ; ( iv ) $ 35.3 million net cash paid for the acquisition of our viridity business ; ( v ) $ 21.3 million paid to noncontrolling interest ; ( vi ) payment of a $ 20.5 million dividend ; ( vii ) a net change in restricted cash and cash equivalents of $ 14.6 million ; and ( viii ) $ 14.3 million of cash paid to prepay our ofc senior secured notes . this decrease was partially offset by : ( i ) $ 245.6 million derived from operating activities during the year ended december 31 , 2017 ; and ( ii ) net proceeds of $ 51.5 million from our revolving credit lines with commercial banks . as described below in “ liquidity and capital resources ” , our corporate borrowing capacity under committed lines of credit with different commercial banks as of december 31 , 2017 was $ 468.0 million , of which we have utilized $ 330.2 million as of december 31 , 2017. critical accounting estimates and assumptions our significant accounting policies are more fully described in note 1 to our consolidated financial statements set forth in item 8 of this annual report . however , certain of our accounting policies are particularly important to an understanding of our financial position and results of operations . in applying these critical accounting estimates and assumptions , our management uses its judgment to determine the appropriate assumptions to be used in making certain estimates . such estimates are based on management 's historical experience , the terms of existing contracts , management 's observance of trends in the geothermal industry , information provided by our customers and information available to management from other outside sources , as appropriate . such estimates are subject to an inherent degree of uncertainty and , as a result , actual results could differ from our estimates . our critical accounting policies include : revenues and cost of revenues . revenues related to the sale of electricity from our geothermal and reg power plants and capacity payments paid in connection with such sales ( electricity revenues ) are recorded based upon output delivered and capacity provided by such power plants at rates specified pursuant to the relevant ppas . revenues related to ppas accounted for as operating leases with minimum lease rentals which vary over time are generally recognized on a straight-line basis over the term of the ppa . ppas with contingent rentals are recognized when earned . 108 revenues generated from the construction of geothermal and recovered energy-based power plant equipment and other equipment on behalf of third parties ( product revenues ) are recognized using the percentage of completion method , which requires estimates of future costs over the full term of product delivery . such cost estimates are made by management based on prior operations and specific project characteristics and designs . if management 's estimates of total estimated costs with respect to our product segment are inaccurate , then the percentage of completion is inaccurate resulting in an over- or under-estimate of gross margins . as a result , we review and update our cost estimates on significant contracts on a quarterly basis , and at least on an annual basis for all others , or when circumstances change and warrant a modification to a previous estimate . changes in job performance , job conditions , and estimated profitability , including those arising from the application of penalty provisions in relevant contracts and final contract settlements , may result in revisions to costs and revenues and are recognized in the period in which the revisions are determined . provisions for estimated losses relating to contracts are made in the period in which such losses are determined . revenues generated from engineering and operating services and sales of products and parts are recorded once the service is provided or product delivery is made , as applicable . property , plant and equipment . we capitalize all costs associated with the acquisition , development and construction of power plant facilities . major improvements are capitalized and repairs and maintenance ( including major maintenance ) costs are expensed . we estimate the useful life of our power plants to range between 25 and 30 years . such estimates are made by management based on factors such as prior

