Solar Panels FAQ

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If you’re looking for a comprehensive solar panels FAQ page (for commercial projects), we answer below a range of questions to help you better understand how solar works, the installation process, and what to expect from Greensphere.

How long does a solar panel project take to install?

Greensphere can generally install a 1MWp installation in six to eight weeks depending upon the nature of the roof, access to the roof and electrical connections and the weather.

What is the lead time to installation?

Evo Energy’s lead time prior to installation is generally of the order of four to six weeks, depending upon design complexity, available information and the size of the scheme for materials. With new build projects, we manage our schedule of works to fit in with your existing project programme.

Is Greensphere responsible for every aspect of the installation?

Yes – Greensphere will be responsible for every aspect of an installation and will clearly define the interfaces between our work and the requirements of our customers.

How important is health and safety during installation?

Greensphere takes health and safety extremely seriously and has one of the best processes in the industry. All our sites can be audited by external consultants on an un-announced visit and the reports are forwarded immediately to the Operations Manager and the Director. Falls from height are a major risk in the construction industry and Greensphere is adamant that it will not contribute to these statistics. Part of our service is that we do a full risk assessment and method statement with each installation.

Are Greensphere’s operatives qualified and do they carry CSCS cards as standard?

Greensphere’s operatives are all qualified where we require a professional qualification and all hold CSCS cards. In addition all Greensphere staff will be identifiable through their standard Greensphere tabards or jackets.

Does Greensphere provide a named manager to supervise the works?

Yes. All works are supervised by a named manager with a first aid qualification.

What commissioning does Greensphere carry out prior to handover?

Greensphere carries out an industry leading process at the end of its works to ensure that the system has been installed correctly, safely and appropriately. This is called the Greensphere PAC process and includes a period of generation, formal sign off and record photographs to conclude our site works.

Do I need to inform my existing energy supplier about an impending installation?

As part of our service, we submit on your behalf a full G59 application and schematic to the DNO (Distribution Network Operator) to get the approval (without this you can’t connect to the grid). This can take up to 8 weeks.

How much energy can I generate from solar panels on my roof?

This is a common question and depends on a large number of variables, particularly on the size, orientation and location of the roof. A simple estimate provides 1,000m2 of south facing roof in the Midlands might deliver 144,000 kWh in the first year of operation.

How long does a solar panel last and does its performance drop over time?

Good quality panels have a life of at least twenty years and when exposed to ultra-violet light their efficiency drops by an average of 0.5% per annum.

How do I connect a solar PV system to my property?

A PV system will be designed to be connected to your main electrical distribution board so that the energy generated can feed directly into your business, replacing electricity that would otherwise come through the grid. Greensphere will generally install a generation meter to see what energy is being generated and inverters to change the DC electricity generated into AC that is capable of being connected to your existing system.

What are the main reasons for installing solar PV?

There are many reasons for installing PV, beyond the key financial reason of a reasonable payback compared to most types of corporate investment. These include the ability to comply with ESOS requirements, reducing a client’s carbon footprint and supporting sustainable initiatives with employees and the local community. View our energy independence area t learn more about the key drivers.

Are there still any subsidies for installing commercial solar PV?

Yes there is some support for installing PV, though the rate is reviewed on a regular basis by the Government. Please contact Greensphere for the current rate of support available. Once registered the support is paid on a pre-agreed rate for twenty years on the amount of energy generated. Please note that there are no other ‘grants’ available at this time.

Do I have to pay for my system or can Greensphere provide a funded solution?

Greensphere is experienced in providing funds from specialist financiers to pay for a customer’s PV installation. In these cases the customer will lease the roof out to the funder and then purchase the generated electricity at a pre-agreed price for a period of between twenty and twenty five years.

Does an Greensphere installation require significant maintenance?

Greensphere prides itself on specifying and installing the best available equipment from a limited and proven set of manufacturers who are prepared to warrant their equipment. However, like any working installation there are benefits of maintaining the system at peak performance and Greensphere can provide a maintenance package for its installations.

How do I ensure the best value for my installation?

The best value is provided by determining what represents value to you as a customer and then insisting on its delivery. At Greensphere we take great pride in our attention to design detailing to ensure that your installation is designed to provide the most efficient outputs possible for the location and that our customer is aware of the options and implications of various design decisions.

Will Greensphere guarantee the performance of my installation?

Greensphere will guarantee the performance ratio of their installations which means that they will guarantee the amount of energy that will be generated in a year relative to the amount of energy that falls on the panels. This guarantee requires a weather station to record the weather during the year and a communications system to inform both Greensphere and our customer of the status at any particular time. This is the only guarantee in the roof top market and demonstrates the conviction and confidence that Greensphere has in its design and installation capability.

What other documentation do I need to claim the feed-in tariff?

An EPC certificate at level D is required to claim the higher level feed-in tariff. We can arrange for this to be carried out if you don’t already have one.

What is a typical payback?

7 years

Do I need planning permission?

Generally no. There are certain exceptions to this. We’ll advise on this and guide you through the process if required.

What equipment is required for a solar PV installation?

A PV installation is essentially an array of PV panels connected to a inverters to change the DC electricity to AC and to put it at the right voltage and phase to connect to a client’s existing electrical infrastructure. This power supply is then run through a safety feature prior to connection to the existing infrastructure. Greensphere’s expertise lies in the design, specification and professional fixing and installation.

What size are most solar panels?

Panels are generally around 1.65m x 1.0m and generate between 200watts and 300watts in optimum sunlight and temperature. Panels are rated to their maximum output and the size of an installation is determined by this rated maximum output multiplied by the number of panels.

Will shading affect the output of my solar PV installation?

Shading has a significant effect on the output, though the newer panels have managed to reduce the effect of partial shade on a system output. Greensphere can do a shading analysis of your installation to determine the effect as part of the design process.

How are panels fixed to my roof? Will they damage my roof?

Panels are mounted on a proprietary rail system that is fixed to the roof. The system is designed to maintain the strength and integrity of your roof, though it is important that the initial roof condition has adequate life remaining.

Are there any external issues that may prevent my installation?

Whilst Greensphere install PV systems to connect to the customer side of their electricity meter the District Network Operator of the electrical grid can refuse our application to install PV. This is done where the local electrical ring main can not absorb any more PV generation without disrupting the grid and potentially other users. This is why one of the first activities that Greensphere will insist on is an application to the DNO to understand if the grid is constrained and our application may be refused.

Does the National Grid have a finite capacity for PV connections?

Yes, the electricity grid can not accommodate infinite renewable generation. The District Network Operators operate a first come first served system for customers wanting to connect PV systems and Greensphere is experiencing customers grabbing this capacity to ensure that their renewable aspirations can be achieved.

If the external grid is constrained then does this mean that I can not install any renewable sources of electrical generation?

It may be possible to install an export limit to a PV system that will reduce the amount of electricity that a site may export to the grid. However, the District Network Operator may still refuse any installation on the basis of the disruption to the existing grid and these refusals may last for years.

Does PV work with other forms of renewable technology?

PV is an ideal partner for battery technology where PV can be used to charge a battery during the day for use at night or during the expensive triad charge periods.

What safety systems are installed?

PV is inherently safe, provided installations are well designed, installed and maintained. Greensphere has been in this market since it started and prides itself on the quality of design, installation and maintenance. There are a number of standard safety features installed on all PV systems, the key one being a G59 switch that cuts off the generation should the mains fail. This allows the Electricity Board to fix a fault without risk of electricity coming back from a PV installation that could harm their repairers.

Is there special equipment for high risk installations?

For high risk installations where the risk of fire needs to be as low as possible Greensphere will recommend a SunPower panel and inverter system where the generation is reduced automatically and locally to a negligible amount in the event of a fault. This provides added security for high risk installations.

How do I know that my panels are performing?

Greensphere recommends the installation of a relatively simple communication system that allows both the customer and Greensphere to monitor performance and check for any faults as they might happen.

How do I know that my roof is strong enough?

Prior to any installation, we carry our a full structural assessment and sign off with a HWA company to ensure wind and snow loadings are within the requirement.

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