Solid State Devices have increased in popularity especially over the last few years, largely due to the large increase in data transfer speeds they afford. It is now common for many computers and laptops to be sold with an SSD and a traditional rotating hard disk drive.
In the last couple of years some scare stories were published in the media, suggesting that an SSD which is not powered may lose the data stored on it with a matter of days. These stories were taken out of context, being based on research involving enterprise level SSDs and excessive temperatures, in which they found data could become inaccessible within only a week.
For normal operation, even for computers only used periodically, this is unlikely to cause an issue, especially as recent research has demonstrated that under average conditions an enterprise level SSD will retain the data for approximately a year when not powered. For consumer SDDs the average data retention time is about double, taking it to about two years.
If an SSD is unpowered and kept in a high temperature environment this average data retention time will decrease, but for most users this will not pose any problems. It would only become an issue in the event of attempting to use an SSD as a long term storage device, where it may spend long periods of time not powered up.
For long term storage of data, it is best to use tape media and traditional rotating hard disk drives, which have a much greater lifespan. This further reinforces the assertion among many computer specialists, that the use of SSDs is best confined to installing the operating system, or part of an enterprise level RAID storage system, where extremely fast data transfer speeds are required.
It must be remembered that all media will deteriorate over time and should be stored at an optimal temperature, in order to give the best possible chance of no data loss. Any data stored on media should be periodically copied, in order to avoid such a problem occurring.