Websec note:- The following items were inspired by the recent talk “Renewable Energy in South Devon”
Lithium-ion batteries
The power of these batteries is also the reason they are so hazardous. In terms of wattage held per kilogram is 50% greater than a traditional battery and 6 times greater than a lead acid battery.
A lithium-ion battery pack consists of lithium-ion cells stacked together in modules, temperature sensors, voltage tap and an onboard computer (Battery Management System) to manage the individual cells. The batteries have a pressure sensitive vent hole in the metal case as a safety measure as they can quickly produce heat under certain circumstances and increase the pressure already built into the battery up to 3000kpa.
They also contain a built-in fuse, but this is not always sufficient to prevent the overheating process as the fuse simply melts. Overheating of these batteries can be caused by many factors including; impurities getting into the battery at the manufacturing stage, poor or damaged connections when either charging or the battery is being discharged, accidental damage to the battery, overheating by outside sources such as the sun, central heating and a fire originating from another source, and age.
Once the overheating commencing a chain reaction occurs and within seconds all the associated cells and batteries can become affected. The least this will cause is a fire but it is also likely to cause an explosion.
Whilst there are certain types of fire extinguisher that can be used it is recommended that only specially qualified people should tackle such fires. If for example the fire is in an electric car it is recommended that the occupants should evacuate the car immediately and get well away from the vehicle in case of explosion.
The concept of much larger storage batteries being located in public buildings that have their own source for generating energy whether from wind or solar is causing great concern. Such batteries , like any battery can fail for the reasons given above then the potential for a massive explosion exists. It should be pointed out that the recommendation to many fire services is that where the batteries are of a certain capacity and type then the fire should be left to burn itself out. The reason for this recommendation is that whilst the fire may be able to be contained the fire and risk of explosion will still exist and thus still presents a highly dangerous hazard to be dealt with.
Following such a fire in Norway the battery was disconnected and put into a large container of water and then driven to a safe area. The battery on being lifted out of the water burst into flames again. Further information available.
The demand for such batteries and the design demands by companies such as car manufacturers means that sometimes safety is not the first priority and the standard of manufacture is sometimes wanting.
The Silent Menace
Infra sound is a very low sound wave usually less than 50 hertz, this is normally too low a frequency for the human ear to detect. However, there is a significant number of people that can hear infrasound as low as 18 hertz and above.
Infrasound is found in the natural environment and is used by numerous mammals including whales and elephants. A whale using infrasound can send out a sound wave that can be detected over 100km away. Elephants produce infrasound to send out a sound wave that not only passes through air but through the ground as well up to a distance of 10km.
Birds likewise are believed to use infrasound to navigate. Various patterns of infrasound that are unique for example, waves crashing on a shore or wind rushing up the side of a mountain.
Infrasound produced by man though is said to be more like white noise such as a radio turned up to maximum but only producing crackling and interference. Electrical turbines electric motors and the blades on a wind generator all produce infrasound. When wind farms are located off shore this infrasound will travel through our oceans for 100’s of kilometres. No measurements are being taken nor any action to prevent this damage. The whale or for that matter any marine creature that relies on infrasound for communication, navigation or finding food will be severely affected. It is like you being made to sit in a room with a radio turned up to maximum broadcasting interference, but unlike you the marine creature cannot get up and leave the room.
Infrasound is also impacting people leaving up to 75Km from an industrial wind farm. Some people can actually here the continual background sound sometimes described as a low humming. The infrasound produced can also travel through the ground and when it encounters a building the wave frequency can cause the walls to vibrate sufficiently to produce a low-level infrasound. It has been claimed that the affect of this infrasound can lead to people feeling depressed and generally unwell. It can bring on headaches that will disappear only if the person spends several hours away from their environment.
Substations also produce infrasound but also a magnetic field in the same way as a pylon carrying electrical cables. The increasing size and capacity of substations means that the force field will significantly increase along with the output of infrasound. People should not spend too much time within a force field and certainly not sleep within its reach.
The windfarm lobby is extremely powerful and can prevent any detrimental information reaching more than a very narrow audience. In a case in Northern Ireland a group of individuals bringing a case against a windfarm consortium had approached a specialist professor in sound energy to provide evidence at the hearing. The university informed the professor that he would not be allowed to proceed as the university received funding from the green energy lobby and had been warned that this would be cancelled if the university or its staff became involved in the case.
Paignton Probus Club 