* Long-term copper price forecast up 8.2 pct at $6,948/T
* China demand seen supporting outlook for prices
* Rising labour, energy costs add cost inflation
By Harpreet Bhal
LONDON, Oct 7 (Reuters) - Long-term copper prices should be boosted by rising cost inflation and a bullish outlook for demand from top consumer China, prompting analysts to revise prices for the next 10 years up by more than 8 percent, a Reuters survey showed on Monday.
The average long-term cash copper price is forecast to rise to $6,948 a tonne, from a previous Reuters estimate of $6,420 a tonne, a survey of 11 analysts conducted over the last three weeks said.
Long-term price forecasts, of 10 years plus, are used by analysts to evaluate what they call the "fair value" of a metal, which helps miners to determine the feasibility and potential profitability of future projects.
These prices tend to be conservative as investors will not commit to a project that only makes money if prices are high. Highlighting the difference between long term and current prices, benchmark London Metal Exchange three-month copper was last trading at $7,207.00 per tonne.
"We find that the cost base has moved sharply higher and marginal cost producers will struggle to survive with prices much below $6,500 a tonne," Standard Chartered analysts said.
"This supports our view that even if demand weakens, there is limited scope for copper prices to fall."
Boosting optimism about the outlook for demand from China was renewed confidence that the country has put a floor under a protracted slowdown in its economy.
To boost activity, its government has accelerated copper-intensive infrastructure spending, sustained spending in public housing and cut taxes for small firms.
https://www.lse.co.uk/macroeconomicNews.asp?code=fmb85q18&headline=LMEWEEKLongterm_copper_price_lifted_by_higher_costs_demand_growth