Exhibit 99.1

Northern Power Systems Announces Fourth Quarter and Full Year 2015 Results

Concludes Previously Announced Financial Restatement

PRESS RELEASE

FOR ONLINE PUBLICATION AND PRINT:

25 July 2016

Year End 2015 Highlights (as compared to restated 2014):

Fourth Quarter 2015 Highlights (as compared to restated fourth quarter 2014):

Barre, VT USA (25 July 2016) – Northern Power Systems Corp. (TSX: NPS) (the “Company” or “Northern Power Systems”), a next generation renewable energy technology company, today announced financial results for its fourth quarter and year ended December 31, 2015 on Form 10-K, which comprehensively completes its non-cash restatement of previously issued financial statements which, as the Company announced on May 24, 2016, should no longer be relied upon. Such filing contains:

The Company believes that it will file both its first quarter and second quarter Form 10-Qs within the month of August and as of such time again be fully compliant with its financial reporting.

“We announced in May of 2016 that we are pursuing opportunities to further monetize our utility wind assets, an effort that will contribute to our focus on profitability for the Company,” commented Troy Patton chief executive officer. “In line with this decision we have commenced streamlining our leadership team and reducing overall operating costs. Within an overall expense reduction plan we are making limited, controlled investments into driving market adoption of our distributed technology and energy system capabilities. With well over 500 distributed units deployed, a fleet of turbines under warranty demonstrating 98% availability and multiple financing sources for customers, our offerings can give confidence and options for the expanding use of distributed energy solutions globally.”

Additionally, Ciel Caldwell, senior vice president for operations and finance stated, “We plan to continue our practice of not issuing formal financial guidance. However, there are certain trends in our business that are important to share. We are seeing revenues being impacted in 2016 by delays in policy clarification and weather in some regions. For these reasons, as well as grid connection delays, our first and second quarter revenues will be markedly lower than our third and fourth quarters.” Ms. Caldwell continued, “Earlier this month, the Italian government published a decree which appears to provide a clear policy structure through at least December of 2017.”

“We are pleased to conclude our restatement process, the nature of which is explained below. Consistent to our original communication, this restatement did not result in any changes to our overall book of business or cash flows. After filing our Q1 and Q2 results in August we expect to re-commence earnings calls with full information communicated to the market,” concluded Ms. Caldwell.

Financial Restatement:

As detailed in the Form 10-K filed by the Company today, management decided to approach the U.S. Securities and Exchange Commission (“SEC”), first on a no-names and then on a formal basis, to resolve the appropriate timing of revenue recognition for certain sales to its international customers. For such sales, the Company’s standard practice had been to recognize revenue at the time the turbine was shipped from its manufacturing facility in Vermont. At that point, title and risk of loss transferred to the customer and a significant portion of cash had typically been collected. Frequently such shipped turbines entered third party logistics customs bonded warehouses contracted by the Company in the customer’s local country to clear customs and await final shipment to the customer’s installation site. In its response to the Company, the SEC concluded that the Company should recognize revenue at the time the turbine clears customs from such warehouses, not at the time of shipment from the Company’s Vermont manufacturing facility.

Based upon discussions with the SEC in May of 2016, management and the Company’s Audit Committee determined that the Company should restate previously issued financial statements for the fiscal years ending December 31, 2013 and December 31, 2014, and the quarters for the fiscal years ended 2015 and 2014, as well as certain quarters in 2013. The Company has determined that the restatement of the prior periods has no impact on the Company’s cash position, cash flow from operations or its overall book of business.

The restatement did result in the following changes to revenues, loss from operations, net loss, and loss per share (in thousands, except per share data, and backlog in millions):

Consolidated Year End Financial Metrics (as compared to restated 2014):

Consolidated Fourth Quarter Financial Metrics (as compared to restated fourth quarter 2014):

About non-GAAP financial measures

To supplement Northern Power Systems’ consolidated financial statements presented in accordance with U.S. generally accepted accounting principles (GAAP), Northern Power Systems has used a non-GAAP financial measure, specifically non-GAAP adjusted EBITDA income (loss). Non-GAAP adjusted EBITDA income (loss) is defined as net income (loss), excluding share-based compensation expense, amortization of acquisition-related intangibles, depreciation of property, plant and equipment, interest expense, tax provision or benefit, and certain other non-cash impacts as applicable.

The presentation of non-GAAP financial information is not intended to be considered in isolation or as a substitute for the financial information prepared and presented in accordance with GAAP. For more information on non-GAAP adjusted EBITDA, please see the table captioned “Reconciliation of GAAP net loss to non-GAAP adjusted EBITDA net income (loss)” included at the end of this release. The table has more details on the GAAP financial measure that is most directly comparable to non-GAAP adjusted EBITDA and the related reconciliation between these financial measures.

Northern Power Systems’ management believes that this non-GAAP financial measure provides meaningful supplemental information in assessing our performance and liquidity by excluding certain items that may not be indicative of our recurring core business operating results, which could be non-cash charges or discrete cash charges that are infrequent in nature. This non-GAAP financial measure also has facilitated management’s internal comparisons to Northern Power Systems’ historical performance and our competitors’ operating results, as well as reflects measurements which are used by creditors and other third parties in assessing our performance.

About Northern Power Systems

Northern Power Systems designs, manufactures, and sells wind turbines and power technology products, and provides engineering development services for energy applications, into the global marketplace from its US headquarters and European offices.

To learn more about Northern Power Systems, please visit www.northernpower.com.

Notice regarding forward-looking statements:

This release includes forward-looking statements regarding Northern Power Systems and its business, which may include, but is not limited to, product and financial performance, regulatory developments, supplier performance, anticipated opportunity and trends for growth in our customer base and our overall business, our market opportunity, expansion into new markets, execution of the company’s growth strategy and timeline for filing the Annual Filings. Often, but not always, forward-looking statements can be identified by the use of words such as “plans”, “is expected”, “expects”, “scheduled”, “intends”, “contemplates”, “anticipates”, “believes”, “proposes” or variations (including negative variations) of such words and phrases, or state that certain actions, events or results “may”, “could”, “would”, “might” or “will” be taken, occur or be achieved. Such statements are based on the current expectations of the management of Northern Power Systems. The forward-looking events and circumstances discussed in this release may not occur by certain specified dates or at all and could differ materially as a result of known and unknown risk factors and uncertainties affecting the company, including risks regarding the wind power industry; production, performance and acceptance of the company’s products; our sales cycle; our ability to convert backlog into revenue; performance by the company’s suppliers; our ability to maintain successful relationships with our partners and to enter into new partner relationships; our performance internationally; currency fluctuations; economic factors; competition; the equity markets generally; and the other risks detailed in Northern Power Systems’ risk factors discussed in filings with the U.S. Securities and Exchange Commission (the “SEC”), including but not limited to Northern Power Systems’ Annual Report on Form 10-K filed on July 25, 2016, as well as other documents that may be filed by

Northern Power Systems from time to time with the SEC. Although Northern Power Systems has attempted to identify important factors that could cause actual actions, events or results to differ materially from those described in forward-looking statements, there may be other factors that cause actions, events or results to differ from those anticipated, estimated or intended. No forward-looking statement can be guaranteed. Except as required by applicable securities laws, forward-looking statements speak only as of the date on which they are made and Northern Power Systems undertakes no obligation to publicly update or revise any forward-looking statement, whether as a result of new information, future events, or otherwise.

Ciel R. Caldwell,

SVP, Operations and Finance

+1-802-661-4673

ir@northernpower.com

NORTHERN POWER SYSTEMS CORP.

CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME

FOR THE THREE AND TWELVE MONTHS ENDED DECEMBER 31, 2015 AND 2014

(In thousands, except share and per share amounts)

NORTHERN POWER SYSTEMS CORP.

CONDENSED CONSOLIDATED BALANCE SHEETS

AS OF DECEMBER 31, 2015 AND 2014

(In thousands)

NORTHERN POWER SYSTEMS CORP.

CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS

FOR THE THREE AND TWELVE MONTHS ENDED DECEMBER 31, 2015 AND 2014

(In thousands)

NORTHERN POWER SYSTEMS CORP.

RECONCILIATION OF NET LOSS TO NON-GAAP ADJUSTED EBITDA INCOME (LOSS) (unaudited)

FOR THE THREE AND TWELVE MONTHS ENDED DECEMBER 31, 2015 AND 2014

(In thousands)