Scrap Eater Sun Composter

We purchased this solar poweredcomposter about a year ago and have been really happy with how fast and easily it composts kitchen and yard waste. Even better is you can decorate the barrel with living plants (we planted strawberries and they are loving it!) and even add worms (we added a few red worms and they are thriving in this mini eco system – “living machine).”

The Scrap Eater is the only truly solar-powered composter. The composting process is accelerated by the warm environment. Using conventional techniques a compost pile at least 3 ft. across is needed to obtain necessary elevated temperatures. To compensate, the Sun Frost Scrap Eater uses solar architectural techniques, glazing and insulation to attain elevated temperatures. The solar heat collected through the dome, along with the heat generated internally by the respiration of the composting microbes is trapped by the insulated walls of the composting chamber. A unique feature of this insulation is its ability to keep the heat in, while it allows oxygen to freely flow to the composting microbes.

The unique shape of the acrylic bubble not only collects solar energy, but channels water to where it is needed most. Water that condenses on the inside of the dome runs down to the plants on the perimeter of the barrel. This process has a dual purpose. First, it reduces the need to water the plants because they are receiving water from the condensation under the dome. Second, the water is flowing to the outer perimeter rather than dripping into the composting chamber, which reduces the moisture level of the compost and the amount of dry material which must be added to the compost.

When the plants growing on the perimeter of the composter mature they will extend their roots to the bottom of the compost chamber and directly extract nutrients and moisture from the composted food scraps. This process continues the natural cycle much like it occurs in the wider biosphere.

…Worms may also be added to the Scrap Eater to assist in the composting process. They help to aerate the soil while producing a very effective soil additive. The compost chamber will typically be 30°F above the ambient temperature and during the summer may be too hot for the worms. To avoid these warm conditions the worms will migrate to the cooler perimeter where the plants are growing. As they migrate, nutrients from the composting area will be transported to the plants growing on the perimeter.


  1. Robin says:

    If you are still looking for questions to answer, I was wondering how you start seeds. I know you like avoid plastic when you can. Do you use plastic trays for seed starting?