General and administrative expenses decreased by $52.2 million during the year ended December 31, 2018, compared to 2017, driven by a $70.3 million decrease in corporate general and administrative expenses. The decrease in corporate general and administrative expenses is primarily due to: (i) the one-off payment in 2017 relating to the success-based advisory fee of $27.0 million paid upon the consummation of the Merger; (ii) a $27.7 million decrease in employee compensation costs driven by $16.5 million in lower stock-based compensation and $11.2 million in salaries and bonuses; and (iii) lower professional fees of $18.8 million, primarily reflecting (a) a $6.8 million decrease in legal services as a result of litigation and transaction costs incurred in connection with the Merger and (b) a $12.0 million decrease in accounting and other advisory services incurred related to AlixPartners LLP fees due to former interim Chief Accounting Officer and Chief Operating Officer support in 2017. The decrease in corporate general and administrative expenses was partially offset by an increase of $5.0 million in technology costs as a result of the implementation of information technology and other critical systems infrastructure.
The increase in the general and administrative expenses of $7.5 million and $4.9 million in our Solar and Wind segments, respectively, were primarily due to higher professional fees. The new Regulated Solar and Wind segment contributed $5.7 million to the total general administrative expenses.
General and administrative expenses - affiliate were $16.2 million for the year ended December 31, 2018, which consisted of a $14.6 million base management fee pursuant to the Brookfield MSA and $1.6 million of rent and other related expenses associated with the transition to our new corporate headquarters in New York. General and administrative expenses - affiliate were $13.4 million for the year ended December 31, 2017, which consisted of (i) a $3.4 million base management fee to Brookfield; (ii) a $4.5 million management fee paid to SunEdison prior to the Merger; and (iii) $5.4 million of stock-based expense related to SunEdison.
Impairment of Renewable Energy Facilities
On March 31, 2018, one customer with whom we had a REC sales agreement expiring on December 31, 2021 that was significant to an operating project within the Enfinity solar distributed generation portfolio, filed for protection under Chapter 11 of the U.S. Bankruptcy Code. The potential replacement of the contract resulted in a significant decrease in expected revenues for this operating project. Our analysis indicated that the bankruptcy filing was a triggering event to perform an impairment evaluation, and the carrying amount of $19.5 million as of March 31, 2018 was no longer considered recoverable based on the undiscounted cash flow forecast. Accordingly, we estimated the fair value of the operating project at $4.3 million as of March 31, 2018, and recognized an impairment charge of $15.2 million within impairment of renewable energy facilities in our consolidated statements of operations for the year ended December 31, 2018 equal to the difference between the carrying amount and the estimated fair value.
We sold our remaining 0.3 MW of residential assets during the third quarter of 2017. Prior to the 2017 sale, we determined that certain impairment indicators were present and as a result recognized an impairment charge of $1.4 million within impairment of renewable energy facilities in our consolidated statements of operations for the year ended December 31, 2017.
As discussed in Note 4. Acquisitions and Dispositions to our consolidated financial statements, on June 12, 2018, we completed the acquisition of the Tendered Shares (as defined in Note 4. Acquisitions and Dispositions) of Saeta for total aggregate consideration of $1.12 billion and assumed $1.91 billion of project-level debt. With greater than 90% of the shares of Saeta acquired, we pursued a statutory squeeze out procedure under Spanish law to procure the remaining approximately 5% of the shares of Saeta, which closed on July 2, 2018 for a consideration of $54.6 million.
Acquisition costs were $14.6 million for the year ended December 31, 2018, and consisted, primarily of investment banker advisory fees and professional fees for legal and accounting services. Costs related to affiliates included in this balance were $6.9 million representing reimbursements to affiliates of Brookfield for fees and expenses incurred on behalf of us (see Note 19. Related Parties to our consolidated financial statements). These costs are reflected as acquisition costs and acquisition costs - affiliate (see Note 19. Related Parties to our consolidated financial statements). There were no acquisition costs incurred by us for the year ended December 31, 2017.
Depreciation, Accretion and Amortization Expense
Depreciation, accretion and amortization expense increased by $95.1 million during the year ended December 31, 2018, compared to 2017, primarily as a result of incremental depreciation, accretion and amortization associated with acquired renewable energy assets from Saeta and capital additions placed in service in 2018.