(Reuters) -Several Apple Inc (NASDAQ:) and Tesla (NASDAQ:) Inc suppliers have suspended production at some Chinese factories for a number of days to comply with tighter energy consumption policies, putting supply chains at risk in the peak season for electronics goods.

But, the two largest chipmakers in Taiwan said that they are currently operating their China factories as normal.

This development is due to tight coal supplies in China as well as toughening emission standards. Analysts say this has impacted the country’s economic growth.

Unimicron Technology Corp, the supplier to Apple said late Sunday that three subsidiaries in China had stopped production between Sept. 26th and Sept. 30 in order “comply” with electricity-limiting policies of local governments.

Taiwan’s manufacturer of printed circuit board said that it does not anticipate any major impact from other production plants.

Eson Precision Ind Co Ltd was an affiliate of Taiwan’s Hon Hai Precision Industry Co Ltd.

Concraft Holding Co Ltd is a supplier for speaker components for Apple’s iPhone. It owns Suzhou City manufacturing plants and said that it will suspend production from Sunday to Friday and then use its inventory to satisfy demand.

Reuters was told by Taiwan Semiconductor Manufacturing Co Ltd and Chipmaker United Microelectronics Corp. (UMC), that there had been no disruption at their China facilities.

“UMC’s Hejian fab in Suzhou is currently running at full capacity utilization of 80,000 plus wafers per month,” said the Taiwanese firm, whose clients include Qualcomm (NASDAQ:) Inc.

Two people familiar with the matter told Reuters that facilities in Kunshan of contract manufacturer Foxconn have seen a “very small” impact on production.

Foxconn needed to adjust only a part of its manufacturing capacity, including the production of non-Apple notebooks. One person added that Foxconn did not experience any impacts at major Chinese production centers.

According to the second source, the Kunshan worker shifts had to be moved by the company in the late September and early October.

Foxconn is a significant Apple supplier.