* Posts Q3 net loss on $1.07 bln writedown charge

* To spend $150 mln more than planned on Permian basin in Q4

* Q3 oil and gas-liquids output up 35 pct

* Lowers net debt reduction target for 2015 (Adds details, background)

Nov 12 (Reuters) - Canadian natural gas producer Encana Corp reported a smaller-than-expected quarterly loss, helped by an increase in oil production, and said it is speeding up capital spending in the Permian basin in Texas.

Encana said on Thursday it plans to spend $150 million in the Permian shale field in the current quarter that was originally earmarked for 2016.

The company said it expects total capital spending of $2.2 billion this year, the upper end of its forecast.

Encana said it now expects to cut net debt by $2.8 billion by the end of the year, lower than its target of $3 billion.

Encana has been restructuring its portfolio to diversify production away from low-value natural gas towards oil, by acquiring new properties and selling some gas-producing assets.

The company in August sold its Haynesville natural gas assets in northern Louisiana for $850 million and said in October it would sell its Denver Julesburg basin oil and gas assets in Colorado for $900 million.

The Calgary-based company has booked impairment charges of $3.62 billion so far this year, including $1.07 billion in the latest third quarter, to write down the value of assets amid a prolonged slump in global crude and natural gas prices.

Encana's oil and gas-liquids production rose 35 percent to average 140,400 barrels per day in the quarter ended Sept. 30. Natural gas output fell 30 percent to 1.55 billion cubic feet per day.

The company reported a net loss of $1.24 billion for the quarter, compared with a profit of $2.81 billion a year earlier.

Encana's operating loss, which excludes most one-time items, was $24 million, or 3 cents per share, compared with a profit of $281 million, or 38 cents per share, a year earlier.

Analysts on average were expecting a loss of 4 cents per share, according to Thomson Reuters I/B/E/S.

Encana's cash flow, an indicator of its ability to pay for new assets and drilling, more than halved to $371 million. (Reporting by Nia Williams in Calgary and Amrutha Gayathri in Bengaluru; Editing by Savio D'Souza)