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How does a Solar PV system work?

A Solar PV system is a renewable energy technology that converts sunlight into electricity to power your home. It consists of solar panels, which are made up of photovoltaic cells which generate direct current (DC) electricity when exposed to sunlight.  This electricity can be used to power appliances and lighting or stored in batteries for later use.

Can I generate electricity from Solar PV even on cloudy days?

While direct sunlight provides optimal conditions for Solar PV systems, producing the highest power output, they can still generate electricity in indirect or diffused sunlight.  This means your Solar PV systems can still generate electricity on cloudy days, although the output will be lower compared to sunny days. Solar panels can still capture diffuse sunlight and convert it into electricity, albeit at a reduced efficiency.  Typically for the same day each year you will generate very similar amounts regardless of the particular weather that year, as the hours of sunlight remain consistent. 

How much maintenance do Solar PV systems require?

Solar PV systems generally require minimal maintenance. Periodic cleaning of the panels to remove dust or debris is recommended, and occasional inspections to ensure proper connections and functioning are important. Solar panels are durable and have no moving parts, reducing the need for extensive maintenance.  Cleaning can be done with water and a very soft brush, or by purchasing specific Solar panel cleaners. 

What happens if my Solar PV system generates more electricity than I use?

If your Solar PV system generates more electricity than you consume, the excess electricity will be fed back into the grid. This is known as exporting which you may receive credits or payments from your utility company for the surplus electricity.  Many people choose to add battery storage to complement their PV array.  This will allow any energy that would otherwise beexported to be captured and stored by the battery. This will allow you to power your home during times of the day with no sunlight or generation from your solar panels. Typically, we would expect that you would make use of around 60-65% of your Solar generation.  With the addition of Tesla Powerwall we would expect this to increase to around 90%, saving you more money on your energy bills.  


What is the lifespan of my Solar PV array?

Solar panels are designed to be durable and have a long lifespan. Most manufacturers offer warranties that guarantee the performance of solar panels for 20 to 25 years, with expected lifespans exceeding 25 years.  With this in mind it’s incredibly important that you are choosing an installer that truly understands the Scottish weather and provides the highest quality mounting system for your peace of mind throughout the year


What is the payback period for a Solar Array?

The payback period for a Solar PV system in the UK can vary based on several factors, including the size of the system, your property location, electricity consumption, installation costs, and available incentives.

As an example, for a 10-panel 4kW array at a cost of £6,500, we can consider a rough estimate of the payback period making a few assumptions:

Electricity Generation: On average, a 4kW Solar PV system in the UK can generate around 3,400 to 4,200 kilowatt-hours (kWh) of electricity per year, depending on panel efficiency, orientation, shading, and location.

Electricity Savings: The value of the electricity savings depends on your electricity tariff and the portion of electricity generated by the Solar PV system. Assuming an electricity cost of 15 pence per kWh, the annual savings can be estimated at £510 to £630 per year (based on generating 3,400 to 4,200 kWh).

Export Tariff: Under the Smart Export Guarantee (SEG) introduced in 2019, you may receive payments for any excess electricity you export back to the grid. The rates vary depending on your energy supplier, and location, with suppliers typically ranging from 3p to 15p per kWh.


To estimate the payback period in the above example, we consider the upfront cost of £6,500, the annual savings of £510 to £630 and the potential earnings from the export tariff of £204 to £252 per year.   Based on these figures, the payback period can range from approximately 7 to 9 years. 

It's important to note that these estimates are rough and the payback period varies based on several factors including variations in electricity prices, system performance, maintenance costs, and any changes to energy policies or incentives.  As part of your design, we can advise on your specific circumstances and provide a more accurate estimation of the payback period of your Solar PV system.

Will I still receive the Feed in Tariff (FiT) payments if I add more panels to my existing array?

The UK's Feed-in Tariff scheme closed to new applications in 2019. These payments were based on the total electricity generated by your Solar PV system, regardless of whether you use it or export it to the grid.

If you are considering adding further panels to your existing array, we can install the new array with a separate new inverter, so that your existing FiT payments aren’t affected.  The new array won’t benefit from the FiT Tariff, however there are Export Tariffs available offering payments for any excess electricity you export back to the grid.


Are there any incentives or grants available for installing a Solar PV system?

If you are considering how to fund your PV and Tesla Powerwall installation, then there are interest-free loans available from the Scottish Government through Home Energy Scotland when taken as a package together with a heat pump or high heat retention storage heaters. They are offering £6,000 towards a PV installation and £6,000 towards battery storage, made up of £1,250 grant funding and £4,750 of interest free loan, paid back over 12 years, for each technology.

With this in mind, Solar PV and battery storage may not be the only renewable measure you are considering as part of your project.  It may be worth considering a Heat Pump as part of your project to make the most of the funding available.  We can complete a desktop survey to include a proposal for Solar PV and a Heat Pump, allowing your project to be eligible for the funding.  

You can also benefit from the Smart Export Guarantee (SEG), which provides payments for the excess electricity you export back to the grid. The rates vary depending on your energy supplier and location.


Can I install a Solar PV system on any type of roof?

We can help with Solar PV installations on most roof types.  A traditional pitched, tiled roof is the most straightforward installation in terms of roof type, making it also the cheapest.  We can absolutely help if your home has a different roof construction.  We regularly install Solar PV on slate roofs, with a member of the team attending ahead of your installation to install the slate hooks.  This does add some cost to your array, but is essential work to ensure your array is secure and your roof remains watertight.

If you have a non-standard roof construction, such as standing seam roof, we may still be able to help.  We will likely require a visit to your home to discuss the installation requirements and complexities.

All of our quotations are subject to survey as every home is different. At the visit we will discuss the location for your array, taking into account your roof type, orientation, shading, and other structural considerations.  We will also assess whether we would require scaffolding to safely access the roof of your property.

If for any reason your roof is unsuitable for a solar PV array, it may be worth considering a ground mounted array for your property.  


What happens to my Solar PV system during a power outage?

If your power outage is during the night, your entire Solar PV system will be powered down. If however you have a power outage during the day your inverter will be powered down but your solar panels will still be generating DC power. If you have a Tesla Powerwall battery system, some inverters may be powered by Powerwall during an outage to allow charging of the battery whilst also keeping the house running. Our company will run through all the safety procedures you may have to do during such event after the installation. Our goal is to keep you safe and informed for your peace of mind during such events.


What are G98 + G99 DNO Applications?

A Distribution Network Operator (Or DNO) is a company licensed to distribute electricity in the UK. These companies own and operate the system of cables and towers that bring electricity from the national transmission network to our homes and businesses. In Scotland this is typically SSE or Scottish Power. 

A G99 or G98 are the applications for permissions that are required by the DNO to connect your Solar PV to the grid. We can manage this with you to ensure that the application is applied for correctly.   Once the offer of connection has been received from your DNO, they will advise if there are any restrictions to the size of your array or any additional upgrade required and the associated costs.  

No work will be carried out without consent from you. We are happy for you to handle the DNO approval, alternatively, we offer this service to deal with the process on your behalf with an administrative charge of£200 +VAT.