Phantom Load

Yours truly is doing a certificate in GLOBAL SUSTAINABLE ENERGY with the University of Florida and what a great experience reading about The History of Energy and Transportation statistics as taught by Wendell A. Porter, Ph.D., P.E. What I will do here is share some of the stuff that I would have learnt and today I will talk of something called Phantom Load.

Chances are, you’ve never heard of the term “phantom load.” What is it and how does it affect you?


In a nutshell, the phantom load is the electricity consumed by a device when it is turned off. For example, your television consumes electricity as it waits for you to hit the “on” button on your remote. The clock in your house uses up energy 24/7 to keep track of time. Devices that have a phantom load are sometimes called “vampires.” These devices have a hidden energy cost that most people are never even aware of. Nationally, phantom loads make up about six percent of our energy consumption. This translates into billions of dollars spent and countless amounts of pollution emitted into our air. Obviously, phantom loads are a huge problem, especially as energy costs rise and our fossil fuel reserves near depletion.




  • Unplug all devices when not in use.
  • Alternatively, plug your devices into a power strip and turn the strip off when you go to sleep.
  • Buy Energy Star appliances to reduce your phantom load for devices that would be impractical to turn off.
  • Tell others about this phenomenon known as phantom load. Chances are, they’ve never heard of it either
  • Watch out for the cube shaped transformers that plug into the wall. These buggers are 60-80% inefficient when plugged in, so it is especially important that these are on power strips.
  • Lead by example. If you start turning off your devices, maybe your roommates or family will too.


  • One study estimated that the phantom load from TV’s alone was equal to the output of a Chernobyl sized power plant
  • A decrease of only 1% in industrial energy use would save the equivalent of about 55 million barrels of oil per year, worth about $1 billion.
  • Nationally, phantom loads make up about six per cent of our entire residential electricity consumption
  • Worldwide, some 2 billion people are currently without electricity

Introduction to Biogas

When animal species ingest (eat food), when it gets to the stomach the bacteria and enzymes in it. This produces gas in the stomach called biogas which contains methane (CH4) as a major component (approx. 70%) and carbon dioxide (CO2-25%) and other trace elements.  Therefore biogas is a technology where organic waste viz kitchen waste, human waste and vegetable waste are made to biodegrade/ferment anaerobically (in the absence of oxygen) to produce a flammable gas and the residue becoming organic fertilizer. With a vast population present on earth it becomes imminent that we start thinking ahead on ways we ought to use to sustain future generation. The first recorded biogas on the continent of Africa was in the beginning of the 1980’s in Guinea. For close to 16 years they were only 60 digesters installed all with an average capacity of 30m3. This whole process occurs in a concrete dome as shown below:


Before feeding the digester, the excreta, especially fresh cattle dung, has to be mixed with water at the ratio of 1:1 on a unit volume basis (i.e. same volume of water for a given volume of dung) and a temperature range of 35˚C or lower. However, if the dung is in dry form, the quantity of water has to be increased accordingly to arrive at the desired consistency of the substrate (e.g. ratio could vary from 1:1.25 to even 1:2). The dilution should be made to maintain a total solid content from 7 to 10%. If the dung is too diluted, the solid particles will settle down into the digester and if it is too thick, the particles impede the flow of gas formed at the lower part of digester. Furthermore, most biogas plants are designed for a total solids content of about 8%. A change of this ratio will have an impact on the HRT (hydraulic retention time) and the hydraulic functioning of the plant. The gas is collected for further use in heating, cooking and lighting. The paste that remains is called slurry and is very rich in nitrogen and hence it becomes a preferred fertilizer/manure.



Although the uptake of this technology is still at a slow pace, there are certain organizations, schools and farms that have led the pack and have greatly lowered their electricity bills using a locally generated product, biogas. A school in Zimbabwe called Monte Casino generates gas from human waste and their toilets are constructed in a way that students’s waste is collected in brick containers acting as digesters (KAWI Series, 1999). It further states that the school generates gas from pigs and cattle. Malawi also has a school called Phwezi Girls Secondary School which makes use of this human waste but the biggest digester measuring 4 000m3 is in Dwangwa, Malawi and the gas is used to distill ethanol. 


With all these benefits, some of you might be wondering then why this technology has not made it in the market with a bang. In the next issue this week I will be looking at some of the economic, social and financial challenges faced by this technology.

The author of these documents is a qualified Fuels and Energy Engineer and can be contacted on for your views and comments.