The average 5 kW pellet stove may use say around 1-3 tons of wood pellet fuel per year. This is a volume that for most people is not too much trouble to lift into the stove by hand with bags. However pellet boilers generally start at 15 kW, for instance our 25 kW pellet boiler will consume around 7 tonnes of wood pellets in a heating season. When it comes to these sorts of volumes many people look towards hoppers and silos to hold the pellets and therefore more automated methods to get those pellets into the pellet boiler hopper. The first method is fixed augers, however in many instances this is not an easy retrofit and can also be expensive. There are also flexible augers, these are easier to retrofit but are not as reliable as fixed augers. Also flexible augers have their limitations due to length and sharp angles. However there is the third option of vacuum systems and you can see a video above of such a system installed by Woodpecker pellet boilers. In the base of the additional pellet store there is an auger. When the vacuum system is turned on the auger will move pellets to the front of the suction nozzle. A fairly small fan can create enough suction to move the pellets through a lengthy piece of pipe. The pipe can go horizontally and vertically making it the most suitable option in many cases to retrofit installations for external wood pellet fuel hoppers. The pellet boiler will monitor the level of the pellet fuel in the inbuilt hopper and if it is running low will turn on the suction fan to pull more pellets through. The only concern with such a system is the potential noise, particularly if the pellet boiler is located close to a living space. Moving from bags to a hopper system with augers and fans etc does cost more but there are cost benefits as well as reduced maintenance and labour. Loose pellets can be purchased cheaper than bagged pellets. The other alternative is we constructed our own pellet storage room with pipes for blown deliveries. We then simply fill a bucket with pellets and load up the pellet boiler. Thanks for reading and please comment.