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TECHNOLOGY - HOW DO THEY WORK?

HOW DO SOLAR PANELS WORK?

Solar Photovoltaics (PV), convert the sunlight into electrical current. Each panel is made up of a number of cells connected together that produce direct current (DC) when exposed to light. The inverters then convert the (DC) into clean grid quality alternating current (AC), for use in the home, with excess fed back onto the grid.

Your PV system is passive in operation, and once installed and operational requires no external input. At nighttime when there is no light, your system will not operate and any electricity you require will be drawn from the grid as normal.

HOW EFFICIENT ARE SOLAR PANELS?

Module efficiency refers to the ratio of output power to input power. In other words: How much electricity can a solar panel produce from a certain amount of sunlight.

So if a solar panel creates a hundred watts of power from a thousand watts of sunlight, it has an efficiency of 10%.

The two main category separations for "most efficient" are:

Lab results vs. commercially available product

Flat-panel vs. crystalline silicon panel

Generally solar panel efficiency ranges from about 6% to over 20%. This is a significant range and it is due to - flat-panel vs. crystalline silicon panel issue. The average efficiency for crystalline silicon ("traditional") solar panels is in the 11%- 13% range. The popular LG 220W panels we offer have an efficiency rating of 13.4% under (STC).

By combining module efficiency with competitive costs per Wp, the systems we offer give high-level efficiency and great value for your money.

WHAT IS SOLAR INSOLATION?

Insolation is a measure of solar radiation energy received on a given surface area in a given time. It is commonly expressed as average irradiance in watts per square meter (W/m2) or kilowatt-hours per square meter per day (kW·h/(m2·day)) (or hours/day). In the case of photovoltaics it is commonly measured as kWh/(kWp·y) (kilowatt hours per year per kilowatt peak rating).

WHAT COMPONENTS MAKE UP A SOLAR PV SYSTEM?

A Solar PV system is comprised of three main components; The solar panels – these convert the suns energy into (DC) electricity, Inverter(s), which convert the (DC) into grid compatible (AC) and a mounting system, which ensures your system stays securely fixed in situ. Other components are; wiring which connects the main components of the system, isolators, these are used to section cut off the flow of electricity throughout the system, and finally a meter that records electricity generated.

Q5: DO SOLAR PANELS WORK IN THE UK, AND DURING WINTER MONTHS?

The first thing to understand about Solar PV Panels is that they don't need a hot sunny day to produce electricity. They only need light. On a sunny cold day, Solar PV Panels will produce more electricity per hour of sunlight than on a hot sunny day because the panels work best when they are cooler.

Even on a cloudy day, there is still plenty of light for Solar PV Panels to produce electricity. This is because the PV cells use both direct sunlight, and also diffused sunlight i.e. the light that is bounced around through dust and clouds.

The sunnier the day, the more electricity that is likely to be generated but the critical thing is the amount of sunlight not the ambient temperature. On longer days, more electricity will be generated but Solar PV Panels still produce electricity when it's cold, cloudy or during the winter months.

WHAT IS THE DIFFERENCE BETWEEN SOLAR PV AND SOLAR THERMAL?

Solar thermal panels convert the sun’s radiation into heat energy, which is then used to heat water directly. Photovoltaic panels convert the sunlight directly to electricity and use it to power the home. It’s a simple as that!

WILL A SOLAR PV SYSTEM HELP THE ENVIRONMENT?

Your Solar PV system can greatly help the environment. It produces no pollution during operation, and by using the sun’s power; you will offset pollution generated by your energy suppliers and the fossil fuels we burn.

PLANNING AND SITING

DO I NEED PLANNING PERMISSION?

As of the 6th of April 2008 most domestic solar Photovoltaic installations fall under permitted development rights, as long as they meet the following criteria:

Solar PV (roof mounted):

> The panels must not protrude more than 200mm from the roof
> The panels must not be mounted on any elevation facing or visible from a highway in buildings in conservation areas and world heritage sites.

Solar PV (Stand Alone):

> The panels must not be more than 4m in height
> The panels must not be installed less than 5m from any boundary
> The array must not exceed a total area of 9m2
> The array must not be situated within any part of the curtilage of the dwelling
> house or be visible from the highway in conservation areas and world heritage sites.

HOW LONG DOES PLANNING USUALLY TAKE?

On average full planning permission will take approximately 8-12 weeks. Solar PV applications tend to be one of the more favorable renewable technologies with local councils.
This is due to their less obtrusive nature on neighbours and the public.

HOW IS EASY IS IT TO GAIN PLANNING PERMISSION?

This is dependant on the size of system you require and the location in which you site the system. With the ever-increasing pressure for the UK to reach targets of 20% of our energy generated by renewables by 2020, most PV systems gain the required permission.

IS MY SITE SUITABLE FOR SOLAR PV?

We recommend a desktop survey primarily to establish fundamental siting criteria, followed by a site visit in order to establish a sites full viability for PV. Some of the key criteria we must establish are:

> Does your roof face between Southwest and Southeast (South is optimum).
> What is the angle of the roof – this must be between 30-40 degrees.
> Is there enough space?
> Is there any shading caused by trees, buildings, chimney stacks etc…
> Is the potential site in a conservation area or attached to a listed building
> Is the roof structurally sound

HOW MUCH ROOF SPACE DO I NEED?

The amount of roof space or land you have available governs the size of system you can have. Due to the versatile nature of solar PV systems and the endless number of possible configurations, we can design a system tailored to fit your site- specific needs.

IS THERE A MINIMUM SYSTEM SIZE I CAN HAVE?

As long as your roof adheres to the relevant criteria for good siting of a Solar PV system, there is no minimum system size. We can design a system to suit your specific needs.

Common systems we offer are:

2.02 kWp System – Area required 17 m2
2.86 kWp System – Area required 21 m2
3.03 kWp System – Area required 24 m2
3.07 kWp System – Area required 28 m2

DO SOLAR PV SYSTEMS CREATE NOISE?

No, they don’t create noise, as they have no moving parts. This is a key reason why Solar PV is a popular technology in the urban environment.

Q8: WHAT OUTPUT COULD I EXPECT FROM A SOALR PV SYSTEM?

This is dependant on the following criteria:

a) The number of panels that make up your array and the kWp value their combined output equals.
b) The direction the panels face. South is the optimum direction; you can site a system anywhere between Southwest and South East, but expect reductions in output.
c) The angle of the panels, will affect the output of your system. Around a 30 degree tilt is optimum in the South of England up to 40 degrees in the North of Scotland.
d) The efficiency of your chosen panels, and the rate at which they degrade over their lifetime.
e) Any shading caused by trees, buildings etc will have a significant bearing on system efficiency.

If the optimum angle is not achievable, you may still expect over 90% of the maximum annual energy yield at 10 degree or 50 degree tilts.

A South facing system can expect to generate around 70% of the maximum annual expected yield.

HOW DO I KNOW IF I HAVE ENOUGH SUNLIGHT?

A PV system needs unobstructed access to the sun’s light for most of the day. It’s important to note, that although it’s better to receive the sun’s direct sunlight it is not imperative as a Solar PV system will still generate on a cloudy or overcast days.

Solar insolation (kWh/m2 day) is a measurement of the amount of energy, in kWh’s hitting a m2 area of the Earths surface. This value changes throughout the UK, and ranges from 850 kWh in the North of Scotland up to 1,250 kWh in the South of England.

GRANTS AND FUNDING

Q1: ARE THERE ANY GRANTS AVAILABLE?

There are very few grants currently available within the UK due to the introduction of the ‘ Clean Energy Cashback Scheme ‘ (FITs) in April 2010. For more details on grants please visit the LOANS AND GRANTS page.

Q2: AM I ELLIGIBLE FOR A GRANT?

To see if you are eligible for a Grant, you will first need to find out whether there are any Grants available in your region. Once you have established this you will then need to make the appropriate applications to allow the relevant Schemes to evaluate your suitability.

Q3: CAN I BORROW MONEY TO FINANCE MY PROJECT?

There are a variety of ways to fund a Solar PV project, some of the options available to you are listed below:

1. Discussing a loan with your bank.
2. Finance Company - Secured lending with security generally taken linked with the FIT. 
3. Finance Company - Unsecured lending with no security taken (Only the strongest applicants).
4. Crofting - A third party (such as Investment Renewabls) will finance the project, you will receive the free electricity and a possible rental fee. The third party financer will receive the FIT payments for total generation and export.

COSTS AND PAYBACKS

WHAT ARE FEED IN TARIFFS (FITS) AND HOW DO THEY WORK?

The FITs provide payments to those who adopt renewable energy, creating jobs & driving the UK towards its obligations to produce 20% renewable energy by 2020, 50% by 2050. The money that funds the FITs comes from the energy suppliers who pass on the costs to their electricity customers. In short, those who don’t install renewable systems pay for those who do!

In order to receive FITs you must asign a FIT supplier, registered with Ofgem (regulators of Gas and Electric supplies). Most people choose to use their current energy supplier as it is hassle free, but you are not obligated to do so. The supplier you choose will pay you the FIT generation tariff for total generation as well as a FIT tariff for any export (minimum of 3.2p/unit as of April 2012) sold back to the grid.

Generation Tariff: You will receive a guaranteed, fixed premium rate per unit (kWh) for total electricity generated onsite.

Export Tariff: For electricity sold back to the grid you will receive a further minimum payment of 3.1p/unit (kWh). You may choose to receive this tariff rate, or you can enhance the value of this payment by negotiating its sale on the open market, up to a value of around 4.5p/unit (kWh).

Bill Saving: When the turbine is generating and you are using electricity, you will bypass the grid, reducing the amount of electricity purchased, making an average saving of 12p 14p/unit (kWh).

DO ALL PV SYSTEMS BENEFIT FROM THE ‘CLEAN ENERGY CASHBACK SCHEME’, FITS PAYMENTS?

No, only solar PV systems that have MCS product certification, installed by an MCS accredited company such as Investment Renewables will be eligible to receive FITs payments.

HOW MUCH WILL A PV SYSTEM COST?

On average you can expect to pay between £3,000 / kWp and £4,500 / kWp. This is dependant on the size of your chosen system and the complexity of your installation. With increased system size (commercial installs) you will pay a reduced £/kWp value.

Due to fluctuations in material costs and the competitive nature of the Solar industry prices change regularly and are ever decreasing. Your site specific needs can alter the cost dramatically and we advise you to CONTACT US in order to receive an accurate system value.

VAT – WHAT RATE APPLIES TO ME?

UK Rates:

Standard Rate – 20% applicable to UK businesses.
Reduced Rate – 5% applicable to Domestic Households.

HOW DO I GET A QUOTE OR SET UP A FREE, NO OBLIGATION SITE VISIT?

The quickest way to arrange a site visit, followed by a quote is to call us. We can carry out a desktop assessment and if your site demonstrates good potential, we can arrange a date and time to visit. If you would like us to get in touch with you, please provide us with your details on our website, using the CONTACT ENQUIRY FORM. You can also contact us using the details below:

Investment Renewables Ltd
Unit 2, 14 Wakefield Road
Grange Moor
Wakefield
West Yorkshire
WF4 4DS

t: 0800 644 6986
e: info@investmentrenewables.co.uk

HOW MUCH ELECTRICITY WILL A SOLAR PV SYSTEM CREATE?

Size, Location, Array Orientation and Siting criteria affect a PV systems electrical output.

Below are some typical systems and their expected outputs in (kWh’s).

2.02 kWp System – Area required 17 m2 – 1900 kWh/Annum
2.86 kWp System – Area required 21 m2 – 2384 kWh/Annum
3.03 kWp System – Area required 24 m2 – 2750 kWh/Annum
3.07 kWp System – Area required 28 m2 – 3084 kWh/Annum

Assume - South facing, 35 degree tilt, no shading, using LG 220 W polycrystalline panels.

HOW LONG WILL IT TAKE FOR A PV SYSTEM TO PAYBACK MY INVESTMENT?

The Feed In Tariff rates differ depending on the scale of the project and whether the project falls under the higher, medium or lower rate. Please see our FITS Explained page for up to date full details, or CONTACT US to confirm the current rates.

DO I NEED INSURANCE FOR MY SOLAR PV SYSTEM?

Yes, you do need insurance to cover against any possible damage or theft. Most home building insurance policies will cover solar panels. We always recommend that you consult your insurer to find out whether or not you have the correct level of cover.

WHAT ARE THE ONGOING COSTS?

There are few ongoing costs once your PV system is installed. You will be provided with an opportunity to take out a maintenance programme upon the completion of your installation. This requires a minimal fee on an annual basis. This is however, optional and a PV system requires little or no maintenance.

DOES IT COST EXTRA TO CONNECT TO THE GRID?

Current regulations require that a system does not exceed 16 amps/phase. Your (DNO) Distribution Network Operator, the people who own the national grid infrastructure, currently allow PV systems up to 3.7 kW’s under a relaxation of the rules. Any systems that exceed this size require a connection application to gain approval that the DNO are satisfied that the infrastructure can accept the given generator. In most cases there will be a requirement to install a G59 relay, an additional level of protection. This usually costs around £2,500 + VAT.

ARE SOLAR PANELS EXPENSIVE?

Solar installations add as little as 4% to the build cost of an average three bed house. This value can be seen in the resale of the property.

By installing solar panels you are future proofing against rising energy costs. This makes your property attractive to those looking for a green, low carbon property, as well as the price conscious.

A retrofit system to an existing property costs from around £8,000 for a 2kWp system. Although this is a relatively high initial cost, the systems are highly reliable with manufacturers warranties in excess of 20 years (panel choice dependant), and with annual degradation of below 1%/annum.

With the benefits of reduced energy bills, security against rising fuel prices and FIT payments, PV can still be seen as a viable investment.

DOES THE ENERGY SUPLLIER I USE MATTER?

Each energy supplier is obliged to pay a minimum rate for each kWh generated and exported for the duration of 25 years.
It is more a question of, which energy supplier can supply you with an appropriate package to suit your energy needs. Investment Renewables are always happy to advise and help you in this process.

ELECTRICAL / CONNECTIONS

WHAT IS THE DIFFERENCE BETWEEN A KILOWATT (KW) AND A KILOWATT HOUR (KWH)?

A kW is a thousand watts and a unit of power. It measures the rate of energy conversion. A kWh is the amount of work done, or energy used, when a kW of power works for one hour.

WHAT IS A KILOWATT PEAK, AND HOW DOES IT RELATE TO A (KW) AND A (KWH)?

Kilowatt peak stands for peak power. This value specifies the output power achieved by a solar module under full solar radiation (under set Standard Test Conditions). Solar radiation of 1,000 watts per square meter is used to define standard conditions.

Most manufacturers also refer to peak power as “nominal power”. Since it is based on measurements under optimum conditions, the peak power is not the same as the power under actual radiation conditions. In practice, this will be approximately 15-20% lower due to the considerable heating of the solar cells.

WHAT IS A GRID CONNECTED SYSTEM?

With a grid connected system the power is fed directly into your main distribution board on the consumption side of your meter so that your appliances use the solar PV systems generation before drawing power from the grid. At times when the solar panels are not generating you will draw your power from the grid as normal. Any excess power generated will be exported back onto the grid with your energy supplier buying this from you at a minimum of 3.1p/unit for redistribution to those who do not have their own Renewable Systems.

WHAT IS A BATTERY CHARGING SYSTEM?

A battery charging system provides you with a continuous power source for your house via an inverter, which makes the power from the Solar panels usable. If you have an off grid site, you would more than likely have a diesel generator on stand-by to cover evening times. (Typically batteries are sized to give you around 2-3 days worth of storage). If there's too much power generated it can be diverted into either water or space heating.

WHAT HAPPENS WHEN THERE IS A POWER CUT?

With grid connected systems current regulations state, if there is a power cut the Solar panels generated electricity must stop flowing onto the grid for the safety of workman repairing the grid or an electrician working in your house. It also prevents damage to the electrical infrastructure around your local area.

IS THERE A LEGAL REQUIREMENT FOR GRID CONNECTION?

G83/1 & G59/2 are the electrical regulations, which apply in the UK. If the solar Array is under 16A per phase then G83/1 applies. If it is over 16A per phase then G59/2 applies. G83/1 requires the notification of an installation to the DNO so they can make a record. Under G59/2 you must gain permission before installing your Solar PV system. Investment Renewables will make the necessary application on your behalf and will liaise with the DNO as part of the service we offer.

These guides are a legal requirement, which all small-scale and large-scale generators must adhere to.

DOES IT MATTER IF I HAVE A SINGLE OR A THREE-PHASE SUPPLY?

No, it doesn’t, our systems can be connected to both single and three phase supplies.

Single Phase:

It is possible to connect a Solar PV system to a single-phase supply. You will require permission from your DNO and a connection under G59/2 with an installed G59 relay more than likely. The G59 relay adds an additional level of protection for the grid ensuring your systems disconnection in the event of a power cut. You can expect an approximate cost of £2,500 for the additional works required. In most cases this will be significantly cheaper than a new three-phase installation.

In some cases it may not be feasible to install under G59/2 and you may be required to upgrade your line and install a new three-phase connection. This process can be costly and one that will require a quotation from the DNO.

Three Phase:

Solar PV systems under 10kw can be connected under G83/1 regulations with the system protection provided within the inverters. Permission is still required but this can be acquired by the submission of a schematic and a generation form. For three phase connected systems this permission is more of a formality

INSTALLATIONS

CAN I INSTALL MY OWN PV SYSTEM?

We do not recommend our customers carry out the installation of their PV systems. This is due to possible damage to panels or the incorrect installation, leaving your roof permeable or panels loose and unsafe.

Our MCS accredited installation team must carry out the connection of the system. This is a requirement under MCS, to ensure the correct level of quality and to guarantee your eligibility to claim FITs payments.

Investment Renewables are fully MCS approved installers of Solar PV systems – MCS installer No – 13767.

HOW LONG WILL THE PROJECT/INSTALLATION TAKE?

A typical project takes between 2-8 weeks from initial site survey to installation completion and commissioning.

Systems up to 4 kWp take between 1-2 days to complete the installation, causing very little disruption to your property or your daily routine. For systems above 4 kWp timescales differ dependent on a number of panels or complexity of installation.

When you receive your quotation you will be provided with a time schedule for your project.

WHY USE INVESTMENT RENEWABLES TO DESIGN & INSTALL YOUR SYSTEM?

Investment Renewables have a vast experience working with PV systems and their integration into your property. We use our knowledge and experience to ensure you get the best out of your system.

> Key reasons to use Investment Renewables:
> To benefit from the lower VAT rate of 5% (Domestic installs).
> Ensure all warranties are validated.
> Working with electrics is exceptionally dangerous.
> Guarantee that your system works efficiently from the outset.
> Knowledge of wind loading, use of quality materials, correct positioning of system components.

MAINTENANCE AND SAFETY

DO SOLAR PANELS GET HOT?

Yes, solar panels do get hot, but not so hot to cause severe damage. Even so, we do not advise you to touch the panels at any point, to ensure your safety.

DO SOLAR PV SYSTEMS REQUIRE MAINTENANCE?

No, due to their passive operation, with no moving parts, a well installed PV system can be left unmaintained. It is however advisable to check the systems regularly, checking all connections and wiring. The owner of the system can carry out basic visual checks, or our trained professionals, for a small cost, can carry out more in depth checks. For more information please CONTACT US.

IS IT IMPORTANT TO KEEP THE PANELS CLEAN?

Yes, in order for a Solar PV system to operate at its most efficient it is very important that they are kept clean. The reason for this is; any shading from debris has an impact across the whole system, causing a reduction in output levels as each panel is connected in series.

The frequency of cleaning is completely down to the owner of the system, but most will clean their system biannually or annually.

Due to the angle of most PV systems (30-40 degrees) the panels stay relatively clean when it rains, as this washes most of the debris off.

If you do wish to clean the panels you should use warm soapy water and clean the panels with a non-abrasive brush, to avoid scratching the panel surface.

WHAT WARRANTY WILL I RECEIVE WITH MY SYSTEM?

Each PV system comes with a 5 year warranty as standard on the installation and product. The LG panels that we offer also come with a 12 year 90% power warranty and a 25 year 80% power warranty. This comprehensive warranty package is one of the best offered by any solar panel manufacturer.

WILL THE SYSTEM REDUCE MY PROPERTY VALUE OR MY NEIGHBOURS?

No, they are likely to add value to your property with the on site generation of free green electricity. They will also promote the properties low carbon footprint and dedication to renewable energy.

A recent survey carried out by MORI found people were willing to pay up to £10,000 more for homes, which are environmentally friendly.

A solar PV system is very unlikely to reduce the value of a neighbour’s property as they create no noise in operation, and most people in the UK are in full support of renewable energy.

WHAT IS THE DESIGN LIFE OF A SOLAR PV SYSTEM?

Solar PV systems have a design life of 30-40 years, meaning they will easily go on producing free clean electricity for many years after the Feed In Tariff finishes.

WILL MY SOLAR PANELS FALL OFF MY ROOF IN HIGH WINDS?

No, our systems follow appropriate guidelines, enforced by the Microgeneration Certification Scheme (MCS) for the correct design of each PV system we install. We calculate the wind loading factors relevant to your location and the size of system you have installed to ensure your system stays firmly positioned for its full operational life.

WILL THE SYSTEM AFFECT THE INTEGRITY OF MY ROOF?

We evaluate every property before installing a PV system, ensuring your roof space provides sufficient support for the additional weight.

If we feel the roof is not up to our standards, we will advise you on any necessary upgrades required.

No, a Solar PV system installed by Investment Renewables will not affect your roofs integrity. Our professional team of roofing experts uses the appropriate fixings and techniques to ensure your roof stays watertight for the duration of the Feed In Tariff.

Using a team with roofing expertise is one of the most important criteria when looking for the right company to install your system, and a must to ensure a hassle free 25 years of solar generation.

SAFETY FEATURES AND ACCREDITATIONS

WHAT IS MCS?

The Micro Generation Certification Scheme (MCS) is an independent scheme that certificates microgeneration products under 50 kW and installers in accordance with consistent standards of safety, quality and performance. Any commercial or large scale systems above 50 kW must apply directly through the Renewable Obligation Order Feed-In Tariff process (ROO-FIT) as they do not qualify under the (MCS).

WHY IS THE MCS SO IMPORTANT?

The MCS is in place to ensure higher levels of quality and customer service. It ensures you get a system that works at its optimum and discourages those without the knowledge and will to serve the customer from entering the industry.

Those of us in the industry who care about the renewable future, our industries development and providing the end user with the highest level of service, are more than happy to promote the MCS and the benefits it brings. This applies to those adopting renewable energy, and to those within the industry acting with high levels of professionalism.

Without Installer MCS and Product MCS certifications in place, you would not be eligible to receive the FITs payments; therefore it is imperative that the company you choose to carry out your installation can provide you with this information.

Investment Renewables MCS Cert No – 13767.

DO YOUR PANELS & SYSTEMS HAVE THE APPROPRIATE ACCREDITIATIONS?

All of the products we sell and promote are fully MCS accredited, guaranteeing your full eligibility to claim FITs payments.

We currently offer LG Electronic panels, SMA inverters, Fronius inverters, Evoco inverters and Renusol mountings. Each of these components is manufactured to the highest specifications, and you can be sure that you are getting a system that will last.

WHAT MEASURES ARE TAKEN TO ENSURE MY INSTALLATION IS CARRIED OUT TO THE HIGHEST LEVEL OF QUALITY?

Investment Renewables have all the correct insurances in place, and follow the guidelines of the MCS stringently.

All the electrical work is carried out by our NICEIC qualified electricians who carry out all work to British standards BS7671 and follow the EII wiring regulations. We also follow the guidance provided by ‘ Guidance to the installation of PV systems – 2nd Edition ‘ carried out by DTI Sustainable Energy Programmes.

Our installation teams have undergone extensive training for each of the technologies we offer, and we pride ourselves on the high level of quality for each installation we carry out.

We have advanced quality procedures that we follow to guarantee every customer is treated efficiently and fairly. Each year, to ensure we are following the MCS guidelines, we are assessed on our quality of installation, so you know that you are investing in the right company and products.

WHAT HAPPENS IF THERE IS A POWER CUT, DO THE PANELS STILL GENERATE ELECTRICITY?

In the event of a power cut, your system will shut off automatically. This feature is built into the system, and is in place to instantly stop the generation of electricity for the duration of a power cut. It protects anyone working on the power lines in the local vicinity from electric shocks. Once the grid supply is switched back on your system will automatically come back on, and continue to generate.