Renewable Energy Introduction

An introduction and guide to Renewable Energy

[email protected]

Glen House, Sigford Road, Matford, Exeter EX2 8NL

• What is Renewable Energy? • Before you start • Solar PV • Solar Thermal • Heat Pumps • Biomass Boilers • Wind Turbines • Hydro Power

Contents

Written by Gareth WaltonWritten by Gareth WaltonSunGift Solar 2012

www.sungiftsolar.co.uk

An introduction and guide to Renewable Energy

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2

Rene

wab

le En

ergy

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2Re

new

able

Ener

gy G

uide

Su

nGift

Sola

r 2

012

What is Renewable energy?When we talk about energy we mean heat or power, something which most of us don’t think twice about, we pay our bills and turn on whatever we need, be it lights, TV’s, computers, radiators, emersion heaters, washing machines, kettles, boilers etc.

Nearly all of the energy we produce in the UK comes from Coal (45%) Gas (28%) and Nuclear (15%). There are two problems, one is coal and gas reserves are running out and we are already importing large quantities from around the world, the other is that as a country we are not producing enough energy for what we need, so effectively we have an extension cable to Europe and we are buying power from France and the Netherlands.

Renewable energy means, making heat and power from the wind, the sun and trees, resources that will never run out. Not only that but this energy is carbon neutral and the Government has made a commitment to reduce our carbon emissions by 50% by 2025 (from the 1990 level).

The technologies we have available to do this are; • Solar PV and Solar Thermal • Wind Turbine • Hydro Power • Biomass boilers

“Electricity can only be stored in batteries, otherwise it flows (like water) down cables so if any power your have generated - with solar, wind or hydro is not used in your home then it will flow out to the ‘grid’ and be used by your nearest neighbour.

There are companies working on domestic battery storage systems for the future but at present these are an expensive option.

In much the same way it is not In much the same way it is not In much the same way it is not easy to store ‘heat’. A room is easy to store ‘heat’. A room is easy to store ‘heat’. A room is ‘heated’ but heat is lost though ‘heated’ but heat is lost though ‘heated’ but heat is lost though walls , windows and doors. Heat walls , windows and doors. Heat walls , windows and doors. Heat can be stored for a while in an can be stored for a while in an can be stored for a while in an insulated water tank. insulated water tank. insulated water tank.

A super insulated and sealed A super insulated and sealed A super insulated and sealed house with a controlled house with a controlled house with a controlled ventilation system is called a ventilation system is called a ventilation system is called a Passive House, these require very Passive House, these require very Passive House, these require very little heat to stay warm.little heat to stay warm.”

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2

Before you start... Know how much energy you use? Note the watts or kilowatts of electrical items in your home.

Reduce your energy usage through energy efficiency measures Don’t leave electric items on when not in use, restrict the use of high powered items, keep doors shut when the heating is on, insulate against losing heat.

Identify any opportunities and/or constraints to renewable energy on your site or property.

Check with your local planning authority whether there are any planning issues (planning permission required for all non-domestic installations).

Select appropriate renewable energy technology or technologies (with the help of this guide).

Get quotes – EST recommends getting three quotes from registered MCS installers.

“First things first. Before we worry about the most efficient way to make energy, we should get a picture of how and when we use ennergy.

Have some idea of how much power different items use in your house. As a simple rule anything that generates heat uses a lot compared to lights. for example a tumble dryer can be 2000 watts (thats 2kWh) and an electric oven can be 3000 watts (3kWh), electric showers can be 9000 watts (9kWh), a washing machine will use a lot of power as it heats water and less as it spins (using a 30 degree wash takes less heating time than a 40 degree wash. Modern low energy lights can be less than 20 watts (so you can have ten lights on for 10 hours (all night) for the same electric power as one hour of tumble dryer.”

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2Re

new

able

Ener

gy G

uide

Su

nGift

Sola

r 2

012

What’s it costTypical annual costs of common domestic appliences Based on 14.5pkWh. Data from carbonfootprint.com

Microwave Oven £13.1596 times per year0.945 kWh per use( mixture of full power/defrosting)

Washing Machine £17.08£17.08187 washes per yearA-rated working at at 40°C using a 2kg load to be 0.63 kWhA-rated working at at 40°C using a 2kg load to be 0.63 kWh

Electric Tumble DryerElectric Tumble Dryer £53.65£53.65148 uses per year148 uses per year2.50 kWh per cycle2.50 kWh per cycleBased on an average load of 4.76 kg of dry laundryBased on an average load of 4.76 kg of dry laundry

Kettle £24.501542 uses per year1542 uses per year0.11 kWh per use based on heating 1 Litre of water0.11 kWh per use based on heating 1 Litre of water

Electric OvenElectric Oven £30.56135.1 uses per year135.1 uses per year1.56 kWh per use1.56 kWh per use

Electric HobElectric Hob £43.64424 uses per year424 uses per year0.71 kWh per use0.71 kWh per use

Dishwasher at 55°CDishwasher at 55°C £17.06110 uses per year110 uses per year1.07 kWh per use1.07 kWh per use

Dishwasher at 65°CDishwasher at 65°C £28.18135 uses per year135 uses per year1.44 kWh per use1.44 kWh per use

Fridge-Freezer A ++ spec £29.8724 hours a day206 kWh per year

Fridge-Freezer A spec £59.1624 hours a day408 kWh per year

Standard Light Bulb £21.174 hours a day100 W

Low Energy Light Bulb £3.814 hours a day18 W

Primary TV – LCD 34-37 “ £72.61On Power6.5 hours a day211.1 W

Primary TV – LCD 34-37 “ £1.66Standby17.5 hours a day1.8 W

Digital TV box/ Recorder £6.06£6.06On Power6.5 hours a day17.6 W

Digital TV box/ Recorder £10.46£10.46Standby17.5 hours a day11.3 W

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2Re

new

able

Ener

gy G

uide

Su

nGift

Sola

r 2

012

Solar Photovoltaic (PV)Generate electricity from daylight, although produce most in direct sunlight.

The South West receives the highest level of sunshine (solar irradiation) in the UK.

Can be supplied as panels or tiles & can be built into the fabric of a building, bolted on afterwards or built on a frame on the ground.

Must be correctly angled & orientated for best performance, with the ideal position facing South at an angle of 30 degrees.

Variation from this will result in reduced performance, but facing between East & West can still be viable.

Shading dramatically reduces performance and should be avoided.

Building’s roof must be able to take the extra weight of the panels

“Although solar PV modules are available in many more aesthetically pleasing forms like tiles that look like slate or sheets of glass, and even flexible roofing membrane, these options are usually more expensive and less productive than the more popular framed panels.

The most productive weather for making electriciy are blue sky days in the spring and autumn when the air is cooler.

Follwing the path of the sun with panels on a ‘tracker’ frame will increase the productivity of panels by some 30%.

A solar system facing directly East or West will still produce 83% of maximum possible when facing south.

Shading in simple terms stops the flow of power through a the flow of power through a the flow of power through a panel and can reduce the out put panel and can reduce the out put panel and can reduce the out put of the other unshaded panels of the other unshaded panels of the other unshaded panels in the same string. There are in the same string. There are in the same string. There are clever inverter systems that will clever inverter systems that will clever inverter systems that will mitigate these problems. mitigate these problems. mitigate these problems.

Panels systems are not heavy Panels systems are not heavy Panels systems are not heavy (19kg/m2) in themselves but (19kg/m2) in themselves but (19kg/m2) in themselves but they are addistional weight and they are addistional weight and they are addistional weight and your installer should be happy your installer should be happy your installer should be happy your roof can take the extra your roof can take the extra weight.weight.”

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2

Solar Water (Thermal) A simple tried and tested technology, water is heated under glass, in the sun on the roof and pumped inside to heat a tank of water.

Solar Thermal has been used in the UK since the 1950’s. Although improvements have been made in production quality and efficiencies.

Once paid for these systems collect free heat from the sun and only need a small electric pump and not much maintenance.

Two main types - flat plate & evacuated tubes. Evacuated tubes are more efficient at collecting the heat of the sun, but also more expensive.

Must be correctly angled & orientated for best performance.

Supplementary heat source such as a boiler or immersion heater usually recommended for when output is low eg in the winter.

The hot water tank and boiler, need to be compatible.

“Flat plate panels can look very attractive (like a velux window) but are a third less effective than evacuated tubes.

Solar thermal systems are ususally not viable if a house already has a gas combi boiler (i.e. no hot water tank).

Solar thermal needs to be plumbed into a coil inside your hot water tank, this usually requires a new tank to be installed - If ever you have to change a hot water tank in your house you should consider if you are ever likely to install solar thermal.

Solar Thermal works very well with a Thermal Store arrangement. This is a larger tank that can be heated from a number of sources (i.e. log burner, heat pump and/or gas boiler) the water is then used for space heating as well as hot water.”

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2Re

new

able

Ener

gy G

uide

Su

nGift

Sola

r 2

012

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2Re

new

able

Ener

gy G

uide

Su

nGift

Sola

r 2

012

Heat PumpsUse similar technology to fridges to extract heat from the air, ground or water.

Can provide space & water heating.

Not strictly a renewable technology as it requires electricity to run and the CO2 and financial cost of this needs to be considered.

A very efficient way of heating as 1kWh of electric input can produce 2.5 - 3.5kWh of heat output.

Provide a low-temperature heat output - best suited to meeting a low heat demand e.g. well insulated properties with underfloor heating.

Ground source heat pumps (GSHP) require many metres of pipe to be buried in horizontal trenches or vertical bore holes. They can even be laid in lakes or rivers (WSHP).

Air Source heat pumps (ASHP) take heat from the air outside and are cheaper to install, but not as efficient as GSHP.

“The efficiencies of air source heat pumps will vary throughout the year. However they can still generate heat even when the temperature outside is minus 15 degrees.

Heat pumps can make a noise when running and are usually sited outside a house, but care must be taken regarding disturbing neighbours.

Heat pumps work well with udner-floor heating as this requires a lowwer operating temperature than radiators.

Water source heat pumps may require approval from the Environment Agency.”

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2Re

new

able

Ener

gy G

uide

Su

nGift

Sola

r 2

012

BiomassBiomass refers to burning wood or other plant material

Biomass boilers/stoves can provide space heating for individual rooms and/or water heating if they have a back-boiler connected.

Larger biomass boilers can provide space & water heating for whole building/group of buildings.

Main fuels are wood chips, pellets, (which are automatically fed into the fire box) or logs.

CO2 and cost savings can be considerable when compared to oil boilers or bottled gas.

Sizing is important as they work best with fairly constant heating demand and working at full load.

Sufficient space for the boiler and for fuel storage is needed plus good access to the fuel store for delivery lorries to access.

Require ash removal, although due to very efficient burning only small amounts produced.

“ A ‘stove’ burns logs or pellets to heat a single room - and may be fitted with a back boiler to provide water heating as well.

A ‘boiler’ burns logs, pellets or chips, and is connected to a central heating and hot water system.

On the basis that we can always plant and cultivate trees - this is a renewable technology.

The carbon dioxide emitted when wood is burned is the same amount that was absorbed over the months and years that the plant was growing. The process is sustainable as long as new plants continue to grow in place of those used for fuel. There are some carbon emissions caused by the cultivation, manufacture and transportation of the fuel, but as long as the fuel is sourced locally, these are much lower locally, these are much lower locally, these are much lower than the emissions from fossil than the emissions from fossil than the emissions from fossil fuels.fuels.

Some appliances particularly Some appliances particularly Some appliances particularly boilers have self-cleaning boilers have self-cleaning boilers have self-cleaning systems built in.systems built in.

These are not susitable for These are not susitable for These are not susitable for smokeless zones.smokeless zones.smokeless zones.

Initial costs for installation can be Initial costs for installation can be high but in the long term savings high but in the long term savings can be conciderable.can be conciderable.”

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2

Wind Turbine Wind turbines harness the power of the wind and use it to generate electricity.

The UK is a windy country and wind is free.

Requires a good average wind speed - A small difference in wind speed will make a large difference to the amount of electricity generated.

Recommend checking average wind speed maps and monitoring wind speeds at the site before deciding whether to install.

Trees & buildings can dramatically reduce wind speed.

Need to be carefully sited, especially in built-up areas, to be effective.

Noise and visual impact may need to be considered.

Annual service needed.

“ Forty percent of all the wind energy in Europe blows over the UK, making it an ideal country for domestic turbines.

There are two main designs of wind turbine – those with a horizontal axis and those with a vertical axis. Most turbines for homes have a horizontal axis. They can be mounted directly on a building but turbines mounted on free-standing towers or poles can be more effective at capturing the winds energy.

Clean wind is best for wind turbines trees and buildings create turbulance that reduce the efficiencies of the wind turbines. Hill tops and open moorland is the best terrain.

The prevailing wind direction needs to be concidered.

Large wind turbines need to be sited away from domestic properties.

Unlike solar power - wind power generation continues at night and during wintertime.”

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2Re

new

able

Ener

gy G

uide

Su

nGift

Sola

r 2

012

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2Re

new

able

Ener

gy G

uide

Su

nGift

Sola

r 2

012

Hydro Power (Water Turbine)Highly site specific, obviously not every one has a river or stream running across their property.

Require a good year-round flow of water & preferably a good height difference between the top of the scheme & the turbine.

May require some civil works i.e. Building work to divert water.

Licences & approval from the Environment Agency are required.

Mitigating measures such as a mesh screen & a fish ladder may also need to be installed.

Noise may be an issue.

Annual service needed.

“ Obviously you need a river or large stream and then the state of the river must not be detrmentally affected by diverting water to a turbine, fish and wild life must be preotected and the Environment agency would need to approve any plans.

You may need to take water from the highest possible point and divert it down a flume or pipe toget enough pressure to turn a turbine.

To ensure the river wildlife is protected you may need a dam and sluice gate.”

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2

Financial Assistance The Government offer financial incentives for renewable electricity, available to everyone – individuals, businesses, organisations & public sector.

F.I.T.A generation tariff known as the Feed-In Tariff (F.I.T.) pays as you generate electricity over time, rather than a traditional grant towards the capital cost.

You are paid for ALL electricity generated whether you use it or not.

The tariff rates vary depending on type and size of system installed. You will get the rate for the lifetime of the tariff at the level on the date you sign onto the scheme. This level is index linked too so the payment keep sup with inflation.

You also get paid for the electricity not used in your house exported to the grid - known as an export tariff.

Better than a grant, this scheme is designed to give you a profit on your investment.

“ The rates of FIT will reduce as the cost of systems reduce over time. Two years ago a 4kWp solar PV system cost £20,000 and the FIT was 41.3p In March 2012 the same system cost £10,000 to install and the FIT is 21p

Income from the FIT is classed as Tax Freee for individuals

Rates of return at March 2012 were equivolent to 7-11%, depending on your invidual properties circumstanceses. A survey from a reputable company will be able to predict your actual rate of return.”

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2Re

new

able

Ener

gy G

uide

Su

nGift

Sola

r 2

012

Guaranteed income for 10-25 years depending on type and scale of technology – index linked.

From 1 April 2012 any new solar PV installation on or connected to a building will only get the full FITs if the building has an Energy Performance Certificate (EPC) rating of D or higher.

The Government is proposing to cut FITs for PV again from 1 July 2012 and also to reduce the tariff lifetime to 20 years.

Tariffs for other technologies are due to be reduced from October 2012.

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2

RHI New Government financial incentive for renewable heat technologies. (Solar Thermal for every one and Biomass, ASHP and GSHP for those off the gas grid).

The RHI is a fund from the Government of £860m to be spent between 2011 to 2014

The RHI is a generation tariff rather than a traditional grant towards the capital cost.

Domestic RHI tariffs currently due to start from Autumn 2012 – no details are confirmed so far.

In the meantime, one-off grants, called RHI Premium Payments will be available from 31 March 2012 for domestic installations only. For further information ask your installer or see the DECC website. - www.decc.gov.uk

“ Properties not on the gas grid can claim for payments towards biomass (£950), ASHP (£850) and GSHP (£1250).

All properties can claim a £300 payment towards a Solar Thermal installlation..”

Rene

wab

le En

ergy

Gui

de

SunG

ift So

lar

201

2Re

new

able

Ener

gy G

uide

Su

nGift

Sola

r 2

012