What on earth is

Bio Diesel?
A greenhouse gas?
A heat pump?
Biomass? 
Tidal Power?

Permaculture ?

Zero Waste Strategy?

What on earth is…a greenhouse gas

A natural “greenhouse effect” is essential  for life on earth. Heat from the sun reaches the  earth, (wishes that there were a few more solar  panels around) radiates back and is stopped  from escaping by a blanket of gases and particles  that act like glass panels in a greenhouse.  They let the sunlight through and keep some  of the heat in the lower levels of our atmosphere. 

Without any of this greenhouse heating  it has been calculated that the earth’s temperature  would be up to 70 degrees below freezing  and the ocean’s would be frozen! 

A greenhouse gas is so-called because of  its heat-trapping properties. There are many  compounds within the earth’s atmosphere  which act as greenhouse gases, some occur in  nature such as water vapour and carbon  dioxide (the two most important in maintaining  our equable temperature), as well as  methane and nitrous oxide, whilst others are  man-made such as hydrofluorocarbons  (HFCs), perfluorocarbons and sulphur hexafluoride. 

The amount of many greenhouse  gases in the atmosphere has increased by a  quarter since large-scale industrialisation  began. The Kyoto Protocol, an international  treaty, set targets to limit the emissions of  these gases and modify their impact on the  greenhouse effect throughout the world in an  effort to reduce their potential impact on  global warming. 

Carbon dioxide is the main greenhouse  gas. It is colourless and odourless. The amount  of it in the atmosphere has risen steadily in  recent history primarily due to the ever  increasing burning of oil, coal and natural gas  as fuels. Worldwide carbon dioxide emissions  are forecast to continue to rise by almost 2%  each year.

Methane is a colourless, odourless  flammable gas that usually comes from landfill  sites, coalmines, oil and gas operations and  agriculture.

Nitrous Oxide is a colourless gas  with a sweet odour, commonly known as  laughing gas and commonly used as an anaesthetic.  It is emitted from burning fossil fuels  and through the use of certain fertilisers and  industrial processes.

Hydrofluorocarbons (HFCs) were introduced  as a replacement for CFCs  (Chlorofluorocarbons) for use in aerosol cans,  refrigerators and air conditioners because  CFCs were breaking down the ozone layer  (which protects us from harmful ultra-violet  rays from the sun). HFCs are non-flammable,  of very low-toxicity and have no effect on the  ozone layer. They are however a potent greenhouse  gas. The most significant source of  HFCs in the UK is the chemicals industry. 

Perfluorocarbons (PFCs) are colourless,  odourless and non-flammable gases which  result from aluminium production, semiconductor  manufacture and leakage from refrigerators.    

 What on earth is…a heat pump

A heat pump can provide a hot water supply  and heat a home in one of the most energy efficient  and environmentally friendly methods.  There are about 1 million domestic heat pumps  working throughout the world and installations  are increasing within the United Kingdom.  One in every four houses in Switzerland has a  ground source heat pump. 

A heat pump works like a fridge in reverse. It  can extract low temperature heat that is stored  naturally in the earth, air or water and raise it  to higher more useful temperatures. Whilst a  conventional domestic heating boiler is about  70% efficient, and a condensing boiler manages  approximately 85% efficiency a heat  pump operates with an efficiency of at least  300%! 

Heat pumps are very reliable, having few moving  parts, and when used in the ground are very  secure and generally not exposed to weathering. 

Heat pump systems have a long life  expectancy, make very little noise, and do not  require a lot of maintenance. They do not  require a flue, ventilation, boiler, fuel tank or  combustion gases. 

Heat pumps are particularly well suited to new  buildings that incorporate high levels of insulation  into their design. In a new, well insulated,  medium sized building the cost of  installing a heat pump system would be  approximately £7,000. Running costs after  installation compare favourably with oil and  electricity powered systems and maintenance  costs are minimal.

Part funding for heat pump  installations is available from the government’s  “Clear Skies” programme (for more  information contact the helpline on 0870 2430  930).  For more information about how heat  pumps work there is an interactive demonstration  model in the Energy Room at the  ATC. Information on the technical and  financial implications of heat pumps can be  obtained from the Yorkshire Renewable  Energy Network co-ordinator, Barnaby  Fryer (01422 846648).    

What on earth is... BIOMASS? 

Biomass is anything that grows, such as  trees and grasses and many food crops, due to  the energy of the sun upon it. (Animal and  human waste are also sometimes misleadingly  referred to as Biomass.)  Energy is usually generated from Biomass  by burning it and it is still the main source of  fuel for the domestic energy needs of more  than 50% of the world’s population. 

Large scale energy generation from  biomass involves the use of crops such as  trees and grasses, as well as forestry and  industrial wood waste as fuel to provide heat  and power.

Willow is a commonly used  biomass fuel although grasses such as  miscanthus, which can only be grown successfully  in temperate regions of the UK, will  produce a bigger biomass harvest per acre  than willow.

Forestry waste is the residue from  the clearing and “management” of woodland  and forests. Industrial wood waste can be  sourced from furniture manufacturers and  carpenters.

Wood pellets are also commercially  produced from compressed sawdust,  ground wood chips and wood shavings. The  use of wood pellets for heating is well established  in North America and much of Europe. 

All biomass fuels will usually be dried,  shredded and chipped before they are fed into  a boiler and burnt. The heat from this combustion  can be used to heat rooms and other  spaces whilst gas is collected from the burning  process and used to produce electricity.

In Ely,  Cambridgeshire, a state of the art straw  burning power station currently produces  31MW of electricity. An increasing number of  farms are using straw-fired boilers for on-site  heating requirements in buildings and polytunnels. 

The Government’s Clear Skies initiative  can provide grants for community household  Biomass schemes.

Contact www.clearskies.org.

 Local wood fuel suppliers can be  sourced via the National Energy Foundation at  www.logpile.co.uk. 

What on earth is....Tidal Power? 

Not to be confused with electricity generated  from waves, tidal power uses the force of  water driven by tidal currents to produce  renewable energy. Tidal power benefits from  the fact that tidal currents are very predictable  (increasing and decreasing in a constant cycle)  and that the water only moves in two general  directions as the tide ebbs and flows. 

The technique of making energy from  tides is one of the oldest, with tidal mills  dating back to Middle Ages in Europe. The  modern-day principle of making electricity  from tidal power is much the same as wind  power. In both cases the amount of energy  produced depends on the speed and volume of  the water or wind. Wind speeds are greater  than tidal speeds but the density of water  (about 1,000 times greater than air) makes  tidal power as efficient as wind power. 

A tidal power station that was completed  in 1966 still generates 240MW of power at St  Malo, France. A smaller facility operates in  Nova Scotia, Canada.

Tidal energy is easier to  convert to electricity than wave energy and  Britain is very well sited to benefit from this  potentially huge power source.  Recent proposals for tidal power plants in  the River Severn estuary would alone produce  almost 7% of the UK’s total electricity  demand. This would be an ideal replacement  for the old nuclear power station at Hinckley  in Somerset that is due to stop producing electricity  (but not radiation!) in 2011.

The  Swansea Bay offshore tidal project, which is  due to begin in early 2004, should supply half  of the town’s electricity needs at a price  similar to the cost of conventional gas-fired  power. 

Unlike traditional "barrage" systems,  modern offshore tidal power schemes involve  minimal environmental impact whilst  producing clean, pollution free renewable  electricity    

What on earth is...Permaculture

Permaculture - A word that that usually evokes an ‘Oh permaculture, I’ve heard of that, what is it?’ sounds like an Alaskan yoghurt or some dodgy biological experiment’.

 Permaculture is in truth an approach to designing systems so that they can be more sustainable. It achieves this by using the patterns and processes of natural systems. Why? Because they are the most sustainable systems we know (having been around for a fair few years) but also because every system in nature is like a cog in a bigger machine, if we re-arrange that cog without taking any notice of what role it plays, the whole machine goes wrong. it's about trying to see the output of the whole system as relevant, not just the individual components.

 Take the example of the recent flooding, among the possible causes are changes made to the way land in the catchment is used. The original forest has been replaced with grass and concrete with no regard to the role it played in the whole river system. The result is that the rivers burst their banks and damage property and business.

 Permaculture does not advocate returning the catchment area to its natural state, humans have to make a living after all, but it would design the area so that we could get what we needed from it without affecting its role retaining water.

 The same philosophy also applies to the role ladybirds play in keeping aphid populations down. Size doesn’t matter. Because natural systems are all linked, they get what they need from each other, using what they have in the most efficient way, thereby reducing waste, over consumption and pollution.

 So how do we do that then? Firstly, by understanding the system you are working with, using good, well thought out design, then looking at how you can get what you need from what you’ve got without clearing it all and starting from scratch. The solutions permaculture finds are often the same as those found by environmentalists looking at recycling, or organic gardeners trying to avoid chemicals. Bill Mollison and David Holmgren who first coined the term Permaculture in the 70’s described it as a philosophy which pulls together past and present common sense. Indeed many of the techniques used are not modern, some of the best ideas for re-using waste were discovered during the war, or by isolated island communities who have had to be self reliant.

 What makes permaculture different is the bringing together of these techniques into one approach, working out a holistic solution which takes into account all the elements so that inputs and outputs are used most effectively.

WHAT ON EARTH IS?…Zero Waste Strategy  

 Following a parliamentary lobby, "Beyond Recycling, Towards Zero Waste", hosted by Liberal Democrat MP Sue Doughty, the UK Zero Waste Charter has been launched by an alliance of environmental groups. It calls on the government to set a target of zero waste for all municipal waste by 2020.

Despite nearly thirty years of often well-intentioned environmental waste policies, huge mountains of rubbish continue to be created and are having an increasingly detrimental effect on all of our lives. Modern-day waste disposal systems that rely on burning and burying large amounts of rubbish commit us to increasing levels of pollution, the loss of valuable recyclable goods, and missed opportunities for job creation.

Unlike traditional waste management policies however Zero Waste Strategy recognises that the continued creation of waste must not be examined as a problem of how to get rid of it, but instead as a way of stopping its creation in the first place! Everyone has a role to play in this strategy but it inevitably shifts the burden of responsibility to producers, designers and suppliers. It also clearly puts waste reduction, re-use, repair and recycling at the top of the waste agenda.
 If a Zero Waste Strategy is adopted there is clearly no need for the incineration of waste or new landfill sites. Products that are wrapped in excessive packaging, goods that cannot be used or consumed in an environmentally sound way and for which there are no safe recycling technologies would be phased out under a Zero Waste Strategy. Producers would be made responsible for the environmental impacts of their product throughout its life cycle and that includes the use of renewable energy sources in its production. A Zero Waste Strategy should be a goal and policy driver for councils and businesses and an aspiration for all households. Individuals have an important role to play by utilising their purchasing power to avoid over-packaged and environmentally unfriendly goods.

Where Zero Waste Strategies have been implemented the results have been amazing. At the Atlanta Olympic Games 85% of its waste was recycled, Honda (Canada) reduced its waste output by 98% in ten years, California has a recycling rate above 50% and Halifax (Nova Scotia of course!) has reached 60%. High levels of recycling and waste prevention are essential parts of successful Zero Waste Strategies but the introduction of new ecofriendly production processes, substitution of non-recyclable materials, material efficiency and extended product life are essential.

The Strategy recognises that the long transitional path to actual Zero Waste will be littered with the debris of traditional residual waste. It proposes to reduce and ultimately neutralise such waste through mechanical and biological treatment plants, which are becoming increasingly widespread in Germany and Austria. Whilst initially criticised for being an unrealistic aim, the value of adopting Zero Waste Strategies is being increasingly accepted as the only realistic and sustainable approach to waste reduction and management.