Is this realistic? I was searching LadyBug feeders and found this. Perhaps some of our techinical experts could chime in? Make Energy From Weeds - All The link above has the entire article. Below is his comparison to LPG Liquefied Petroleum Gas (LPG) versus Biogas Another test to find out the actual efficiency of the biogas is to compare with Liquefied Petroleum Gas (LPG) normally used in our household. In our home, a full LPG cylinder containing nearly 15 kilograms of gas normally lasts for about 30 days. So, our consumption works out to about 500 grams of LPG per day. As you can see in the pictures above, I have placed both the systems (one using LPG and another with Biogas) side by side. On 13 October 2014 we installed a new LPG Cylinder and started using both LPG and Biogas simultaneously. The LPG cylinder was fully emptied on 24 November 2014 and replaced with a new one. The LPG cylinder which normally lasts for only 30 days has now been utilized for 41 days in conjunction with Biogas. At the rate of 500 grams of LPG per day, the additional 11 days X 500 grams = 5500 grams of equivalent LPG has been supplemented by Biogas. Production of Biogas per day from weeds equivalent to LPG = 5500 grams /41 days = 134.15 grams So, 0.226 cubic meter of biogas produced everyday ( mixed with Carbon Dioxide, Nitrogen and Hydrogen Sulfide), gave us 134.15 grams of equivalent calorific value of energy in comparison to LPG.