FAQ
Frequently asked questions
Our grid connected systems start from around 1kW peak power, this occupies between 5 to 6.6 square metres on your roof.
For every kW of peak power installed on a South facing roof the system will generate around 800 kWh. This reduces by around 15% for an East or West facing roof.
There is no VAT applicable to the cost of installing a domestic solar or battery system. Commercial users will have to pay VAT as normal.
For the domestic market the install prices start around £1000-£1500 per kw power depending on the type of panel, inverter and the complexity of the installation. For commercial installations this price can be considerably lower.
Within certain criteria our roof mounted systems do not need planning permission unless the property is listed or in a conservation area. Some flat roof installations may need planning but the planners generally look favourably on Solar PV. If the system is to be ground mounted then permission will be needed if the system is over 9m sq. That's about 5 panels.
Greencap Energy Ltd is certified to self-certify the electrical and structural elements of a domestic PV installation, and will notify building control once the system is installed through our certification bodies.
Most roofs are strong enough to take a solar installation without any reinforcement, however we will carry out a full survey of your property and consult our structural engineers if required.
No, you do not need to inform your electricity supplier but you may need to inform the DNO (national grid). For systems below 16 Amps we will inform the DNO once the installation is complete. For systems larger then 16amps you will require permission in advance from the DNO. We can arrange this if needed. Larger properties may have 3 phases supplies from the grid and in these cases, we can install up to 11.04 kw without permission.
We have had clients report that their system will pay for itself within 4 years. This however is unusual and we would say 6-8 years should be achievable. Ultimately it will depend on how you use the electricity generated.
All unused electricity will be exported back to the grid. You can apply to any supplier (it doesn’t have to be your supplier) for them to fit an export meter. We cannot by law fit this export meter. If you have a battery fitted the excess electricity will automatically fill the battery before any exportation.
A battery can be added to any solar installation to capture any excess electricity that the building is not using. Battery’s in fact can be installed without having a solar installation where they will take advantage of the cheaper rates. However we are not prepared to guarantee that these cheaper rates will be forever.
A kWh (pronounced ‘kilo watt hour’) is a specific amount of electricity. 1 Kwh is identical to 1 unit of electricity that is shown on your electricity bill. An electrical item having a rating of 1kW will consume 1kWh for every hour it is on at full power.
The solar photovoltaic panels generate direct current (DC), this is not directly compatible with the 240V alternating current (AC) that is used in your property. The inverter converts the DC power to AC power that can be used in your property.
We connect the system to your fuse board (consumer unit). The electricity will automatically flow from there to wherever it is needed. If you think of two hoses, one being high pressure and the other low pressure. The electricity you generate is like the high pressure hose. It surpresses the low pressure from the grid. Therefor it will only let the grid (low pressure) onto the fuse board if you are useing more that you are generating.
For the safety of the workmen working on the grid, Solar PV systems do not operate during power cuts. However, there are some battery systems that can supply a certain amount of power in the event of a power cut.
Systems up to about 9kw peak power can sometimes be accommodated on a single phase electricity supply, however we do need to seek permission from your Distribution Network Operator (National Grid).
We do not include for scaffolding in our prices unless there are specific requirements for us to do so.
We cannot see the PV systems dropping much if at all in the future. However, batteries may become cheaper with new technology.
Often not, the efficiency of a panel relates to how many watts a panel will produce. Only when suitable roof area is at a premium does it make sense to choose high efficiency panels, this will maximise the amount of power that can be generated from a roof. Greencap Energy can supply high and standard efficiency modules. Ultimately a 4Kw system is a 4 kw system. It can be made up of lower efficiency 250w panels of high efficiency 340w panels.
-Typically, we use high quality panels from Various manufactures but we always try and supply a panel that suits our customers’ requirements in terms of price, guarantees, manufacturer and looks.
Panels generally have a product guarantee of 12 years and an output guarantee of 25 years. Inverters and battery’s normally have a guarantee of 5- 10 years but warranty extensions can be purchased. Most other components are guaranteed for two years which like our labour is covered by our warranty insurance. Check your quotation for specific details or ask.
We only use the very highest quality of materials. The panels we use meet all the required standards including TUV and MCS approval.
No, all roof work will be completed by our trained roofing specialists. We use our electrician for electrical work and our roofers for roofing work.
For standard roof we use rigid aluminium brackets that are fixed directly to your roof rafters. The brackets hook out from underneath your existing tiles. The rail is then attached to the roof hook and the panels attached to the rail. We do not drill tiles/slates or use mastic/silicone to weather proof your roof as these techniques do not have a long-life span.
On residential properties a system will normally take a day to fit the panels. After they have been fitted properly, our qualified electrician will visit you within a few days to connect the system.
Normally about 13kg per m2.
Solar PV panels are very robust and can withstand the normal stresses subjected by nature.
Once the panels have created electricity you could connect this to an immersion heater to heat water via a diverter. Ask us for more information about controllers available for this.
Our roofers and electricians are all employees of Greencap Energy.
A battery can be added to any solar installation to capture any excess electricity that the building is not using. Battery’s in fact can be installed without having a solar installation where they will take advantage of the cheaper rates. However we are not prepared to guarantee that these cheaper rates will be forever.