Category: Technology

Wave Energy – An Ocean Full of Potential

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Wave Energy - An Ocean Full of Potential

Wave technology Wave Energy also known as ocean wave power, is another type of ocean based renewable energy source that uses the power of the waves to generate electricity. The Earth has not been called the "Blue Plant" without a good reason. Nearly three-quarters of the plant is covered in water, so it is only natural that the search for a clean, renewable source of energy should lead us to the oceans around us. Using the potential energy stored in the oceans and seas to generate electricity ensures that power being generated will be pollution free. Using the power of the waves and ocean currents is not new as wave, tidal and hydro power has been used for many thousands of years. What is new however, is the way in which we now harness, store and generate electricity from it. Making use of the energy that can be produced by the ocean waves is not easy as the worlds oceans are obviously vast. But these oceans contain a massive amount of usable energy just waiting to be tapped. One only needs to look back a few years to the tsunami in Japan to understand this. While it is clear there is plenty of energy present in the oceans and seas, the question is whether we can convert this stored energy into a continuous renewable energy source. The answer is we are already starting to. Unlike tidal energy which uses the ebb and flow of the tides, wave energy uses the vertical movement of the surface water that produce tidal waves. The oceans waves are full of kinetic energy (movement) as they move around the oceans, and it is this energy which can be used to power a turbine or an electrical generator. Wave energy collection is a passive process in which the energy of the waves is automatically converted by turbines. This type of renewable energy source is also environmentally friendly, as it creates no atmospheric pollution and has a small carbon footprint. While the oscillating motion of the waves may be the same around the oceans, there are a few different ways in which we can harness the energy from the moving waves. Wave power converts the periodic up-and-down movement of the oceans waves into electricity by placing equipment on the surface of the oceans that captures the energy produced by the wave movement and converts this mechanical energy into electrical power. The four main types of wave energy devices are: Point Absorbers - which are tethered to the ocean floor. Wave Attenuators - which are long horizontal semi-submerged snake-like devices. Oscillating Water Column - which converts wave energy into air pressure. Overtopping Devices - where the sea waves are driven up the ramp filling-up a small tidal reservoir. These four types of wave energy devices need not be placed way out into the oceans to benefit from the power of the waves. Depending on the distance between the wave energy conversion device and the shoreline, there are three possible locations were these four energy converting devices can be placed and these are classified as: shoreline, nearshore and offshore. Each location and energy conversion device has its own advantages and disadvantages. Wave energy has great potential as Mother nature provides a large supply of renewable wave energy every day. The technology already exists for extraction of this free energy as there are many wave energy conversion devices in the oceans around the world at this time generating renewable energy, but there but there is still a long way to go as there are many technical challenges to be solved. One of the challenges to overcome in using the energy of the waves is that the ocean waves, although consistent in the fact that the worlds oceans are constantly moving (especially near coastal areas), they are variable as weather conditions and seasonal changes affect wave height. Another major challenge to effectively harnessing the energy is figuring out a way to construct devices that can survive the harsh oceanic conditions as some devices have already been destroyed by the energy carrier itself: "the sea". However, if the technology and efficiencies are improved offshore wave energy can provide many advantages compared to other forms of renewable energy sources. One of its main advantages is that wave energy is generally considered to provide a clean source of renewable energy with limited negative environmental impacts with very low or zero CO2 emissions. Wave energy also has negligible land use and large scale implementation of wave power technologies could help stimulate declining shipbuilding and dockyard industries that could help fabricate these metal bodied wave energy devices. Despite the challenges of harnessing the power of the waves, there are still plans to build wave energy farms throughout the world. Like battery charger power, wave power is completely green, completely clean and completely sustainable. The challenge is to figure out how to do it effectively, efficiently and economically.

The Renewable Industry Could Destroy Hull

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The Renewable Industry Could Destroy Hull

At the moment all we are hearing is about it how great Siemens and the wind turbine project is for the city of Hull. When I spoke to Sam Pick, director of The Renewables Network, he described it as 'an opportunity of a life time for this region.' I agree that it certainly is the case, but if Hull is not careful the economic boost from this multi-billion pound industry will all go offshore. If this happens it could destroy the town's opportunity for long-term business growth, leaving its tattered remains on the side of the bank of the Humber. Looking out to sea at Green Port Hull and The Enterprise Zone wishing they could have been a part of it all and wondering what on earth happened. Did you know that the Siemens part of this project is the third phase of the project and that the first two phases have come and gone with locals getting very little of the business from it? Phase three is by far the biggest part of this wind farm project but what I'm asking is 'what are you doing differently compared to phases one and two to benefit from it?' Do you want your business to grow and be financially comfortable for years to come or do you want to be left complaining that you never got a fair go, which is what happened with the other projects in the North Sea in the 70's and 90's? I am an Australian living in Hull so I can give an outsiders view on what I see going on. What I see is a group of European businesses coming over here and stealing the profits and livelihoods of the hard-working business people of Hull. Green Port Hull is the manufacturing and export facility of offshore wind turbines set up by Siemens. On their website they've said that Green Port Hull has the potential to be the single biggest influence on Hull's economy for generations. The key word there is 'potential' and that means nothing unless you change how you think and feel about taking advantage of the opportunity that is available. I say this because even though our government and our local council have given 30 million pounds to Siemens to build the thing here, most of the business is currently going to other countries in Europe. It sickens me to see this great town, that is steeped in history and that I now call my home, getting treated in this way. We have a chance of making the most of this fantastic opportunity but first we need to change the negative attitudes as I have witnessed in the average person in Hull. So many people are lacking pride in our city, they have limiting beliefs that this success is possible, they feel hard done by, and they feel that they are owed for the loss of the fishing industry as well as the lack of support after the bombings in World War 2. Do you know anyone who shares some or all of these beliefs? If you do then I have something to let you know. If things don't change then what we have seen in phases one and two will continue to happen in phase three. The Europeans, mainly the Danish, will come across the water on their Viking ships and they will steal from you once again. You will be as helpless as before to do anything about this unless you arm yourself with the right mindset, the right tools and the courage to fight for what is rightly yours! It is my passion to help this picturesque city with its white carved fountains on the roundabouts, the majestic structure of the Humber Bridge and the fabulous KC stadium. In this sporting year I am teaching the business people of Hull to develop and train their mind muscles to go the extra mile, to train when others aren't, and to get ready for the race of their life. To be ready so that when that gun goes off they will have the culture and capacity to out bid, out work and outperform the European threats to win their own gold medals for their town and country! There are old businesses in Hull that have stopped growing and have gone stale. There are new businesses that are struggling to get going. There are also businesses who just don't know what to do next to survive. Are you one of those businesses? Are you wondering what it is you need to do turn things around? Are you desperate for a bit of good fortune to get your business through these tough economic times? Well the age of The Renewable Industry is among us and this wind turbine project can give this previously unlucky city the bit of luck it has been waiting for. I'm ready to help anybody who wants it or needs it. The Renewable Industry could destroy Hull but it is up to people like you and me to stop that from happening. The real question is 'are you ready to do what it takes to grow your business and reap the financial rewards for many years to come?'

High-Performance Engineering Applications

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High-Performance Battery Engineering for Undersea Applications

Increasing demands are being placed on battery power for undersea applications such as vehicle propulsion, operating portable equipment such as cameras or measurement devices, and operating installed equipment such as telecom infrastructure. Factors such as longer missions and higher peak-energy demands from more sophisticated and intelligent systems call for greater energy density, improved reliability, greater safety and high resilience to the elevated pressures experienced in undersea environments. Overall, the design of the battery system must ensure high levels of reliability and safety, so as to minimize danger to personnel as well as disadvantages such as property loss, down time, mission failure, and high maintenance costs resulting from battery failures in the field. Lithium battery technology has several advantages over other types, particularly its higher energy density. However, creating a lithium-based battery system capable of delivering the optimum performance and meeting reliability and safety-acceptance criteria, at the right price, demands careful attention to aspects such as cell technology, cell balancing, charge control and production quality. This white paper describes these issues and discusses potential solutions that can be built into a lithium battery pack for undersea applications. Preferred Battery Chemistry Modern undersea missions require battery chemistry offering significantly higher energy density than existing chemistries such as Lead-Acid, Alkaline, Ni-Mh, or Ni-Cd. This is necessary to supply all the energy requirements of modern equipment, and to support longer manned or unmanned missions. More modern lithium-metal and lithium-ion (Li-ion) battery technologies have matured and now offer up to four times greater energy density than the older technologies. They also overcome many of the associated limitations, particularly those related to operating or charging the battery in sealed conditions during use. Applications and Environment Because water has its densest phase a few degrees above freezing, temperatures near the sea bed are generally in the region of 4-5AC. This is comfortably within the usual operating range of a lithium battery. The pressure experienced by the battery pack can be very much greater than normal atmospheric pressure, depending on the depth at which the equipment is required to operate. The pressure exerted on equipment operated near or on the sea bed can be as high as 10,000 psi. High outside pressures are capable of deforming the battery casing and bursting seals, leading to effects such as contamination of the electrolyte and failure of the battery. To combat this, the battery pack and other subsystems may be mounted in a pressurized container, depending on the application, to minimize the pressure exerted on the battery module including any internal control circuitry. Lithium batteries are known for their suitability for use under high pressures in oil-filled or potted enclosures. For example, within other critical markets such as the down-hole oil and gas industry, lithium packs are operating in harsh applications where extreme pressure, high shock and vibration are commonplace during drilling and measurement operations. A suitable battery system for sub-sea applications must be able to operate below the surface in a sealed environment. Lithium-metal, Li-ion and Li- polymer batteries provide an ideal solution as they can be recharged with no need for venting, since (unlike lead-acid or Ni-Cd batteries) the battery generates no gases during recharging. Since there is no need to disturb the sealing mechanism, the risk of early seal failure is greatly reduced and batteries can be recharged more easily on the surface or in situ, if required. As with all cell chemistries, lithium-type batteries are not immune to failures in the field. There is a risk of fire or explosion if lithium batteries are overcharged or allowed to overheat. Some high-profile failures have been seen in the computer industry, which have resulted in the recall of large numbers of notebook PCs. The main causes of lithium battery failures are overheating, overcharging, and imbalances between cells. Proper control of charging, including temperature monitoring, is therefore essential to ensure robust and reliable performance in mission-critical applications. The rate of charging, for lithium battery technologies, is relatively inflexible, and is typically around 1C or less. The battery is initially charged at maximum charge current until the rated voltage is reached. The current then falls as the maximum voltage is reached, and charging terminates when the current falls to below 3% of the rated value. The maximum voltage for a lithium battery is typically around 4.1V-4.3V per cell. Overcharging to a higher voltage can cause instability, gassing and temperature increase giving rise to risk of fire. For this reason, protection circuits are implemented to prevent excessive charge voltage from being applied and to halt charging if the temperature increases to critical levels. It is also important to provide circuitry that will protect the battery against becoming over discharged, by shutting down the system when the battery voltage reaches a minimum level. This is typically in the region of 2.7V-3.0V per cell (in the design phase, it should be considered that, although the charged voltage is a nominal 4.2V, the typical on-load voltage may be reduced to 3.2V to 3.3V). Circuitry to control charging and prevent over discharge can be implemented externally, in a battery-specific charger, or internally within the battery itself. Either approach may have advantages: external charge control may permit smaller, lower-cost batteries; on the other hand, integrating the circuitry allows a variety of energy sources such as a DC power supply or a fuel cell (or a combination of sources) to be used more easily.