7 Things You Should Know About Installing Solar PV Rooftop


How does the Solar Rooftop PV work?

Basic knowledge about Solar PV Rooftop System

Solar Rooftop Solar Power System is a power generation system that can be installed for residential houses. Office building, factory building, car park roof, which the system will produce electricity for use in conjunction with the distribution system of electricity. Helps to reduce your monthly electricity bill effectively.

Solar power generation system of the Solar Rooftop solar cell transforms the direct current into AC power with the inverter and then connects to the electricity distribution system of the Metropolitan Electricity Authority. Or Provincial Electricity Authority The advantage is that electricity can be sold to the Electricity Authority. (This must be approved by the government agency first) or use the electricity that has been used to reduce electricity bills. If the production is not enough, the control equipment will bring electricity from the electricity distribution system of the electricity to use instead.

Important equipments of Solar PV Rooftop are

  • Solar Module
  • Mounting Structure
  • MDB Solar to Main Owner
  • Grid-tie INVERTER

Basic maintenance of a Solar PV Rooftop

Cleaning The right way

  • Read the guide of the solar panel clearly. How to clean.
  • สExploring that the circuit has been closed And explore that no part of the panel is damaged, the power cord joints, if loose then tighten.
  • Picking up the twigs, leaves and trash that are blown out of the panel and cutting the branches that cover the panel as appropriate
  • Clean with cloth Or warm foam Mixed with non-corrosive cleaners.


Which type of Solar PV Rooftop is right for you?

Solar PV Rooftop installation

For selling electricity to electricity authority

“You must have a contract to sell electricity to electricity authority”

This type of installation is to produce electricity for the Metropolitan Electricity Authority. Or Provincial Electricity Authority The meter must be installed separately from the meter that we use for electricity. However, the purchase of fire must depend on the government's policy on when to register for the distribution of electricity and how much the electricity cost is to be paid. Which last closed in June 2015

For self-power

“Houses or factories that want to reduce electricity bills”

Installation of this type to reduce electricity bills When using lights More than those produced by solar cells, the Grid-Tie Inverter device connected to the electricity distribution system Will act to automatically pull electricity from electricity Therefore, it will reduce the electricity cost and there is not enough power limitation due to pull from the electricity to compensate.

Which is suitable for factories that have electricity costs ranging from 50,000 baht or more for factories that are already using loads during the daytime If using your own money to invest There will be a payback for about 6-7 years, but for those with good performance With continuous profits Able to lease machinery (Leasing) instead of investing itself, as “You don't have to spend money” Or invest no more “10%”


Solar PV Rooftop
Can be installed on all types of roofs?่

Solar PV Rooftop installation

All types of roofs can be installed with solar panels, both metal sheet and roof slab, because the roof is a part that receives very little strength. Normal solar panel devices installed on the roof Will have a load of about 10-12 kg per square meter.

  • Made with materials, wood, iron, boxes or rails, etc?
  • How much size?
  • What is the lifespan?
  • Roofing sheet type And the approximate weight per square meter

After that, consult a structural engineer. In order to see how much the roof can be loaded, it can be said that solar cells can be installed.่

Installation restrictions

  • The installation area should not have shadows such as shadows from tall buildings or large trees.่
  • Not suitable for roof structures that cannot support the weight of equipment, such as wooden structures.
  • Not suitable for zinc roofs or double roofs that are about 10 years old

System warranty

Warranty / Before - After installation Service

PV Solar Panel According to the standard must be as follows

  • 10 years product quality guarantee
  • Guarantee the efficiency of the panel according to IEC Standard are
    • Efficiency must be reduced by no more than 10% within the first 10 years
    • Efficiency must be reduced by no more than 20% within the first 20 years
    • Lifetime of the panel, Mostly will stay up to 25 years

Solar Inverter

Should have product quality assurance for 5 years when in warranty terms Must have a new inverter immediately

System warranty

After the check has been delivered If there is any defect or damage that causes the system to not work properly and is unable to produce electrical energy from the solar rooftop system, the company will proceed in accordance with the O&M agreement. The company will check the system every 6 Month


Tax benefits and BOI

Value investing

Tax benefits

In the calculation of income tax for 2017 * use the right to invest in the property "Solar Roof" can be deducted as expenses 50% of the investment for calculation of PND 50 for the year

Tax benefits (BOI)

  • Can reduce corporate income tax for 3 years, worth up to 50% of investment
  • Used to reduce import duty on machinery No VAT for imported machinery

Permission and action
Before - After installation

Basic knowledge about the system Solar PV Rooftop

When the applicant sells electricity through the selection process from the MEA or the PEA, the vehicle can begin to request permission under various laws. Related as follows

Requesting permission before installing Solar PV Rooftop

  • Application for a building modification license (อ.1)
  • Application for a license to operate an electric power plant (ร.ง.4)
  • If the building is located in the area of the Industrial Estate Authority of Thailand (กนอ.)

Requesting permission after installing Solar PV Rooftop

  • Application for a license to produce controlled energy (พค.2)
  • Notification of the energy business operation that is exempted from the need to apply for a license

Download related documents at Energy Regulatory Commission website (ERC)


Government policy on renewable energy

New Power Development Plan of Thailand

The guidelines for the preparation of the new PDP plan are in accordance with the main principles that the NEPC meeting has provided under the 3E pillars, namely่

  • Energy Security
  • Economic
  • Environmental Friendly

Download related documents at Energy Policy and Planning Office website (EPPO)


What is TOU?

Time of Use Rate - TOU

The Time of Use Rate (TOU) tariff is applied since January 1, 1997, while the On Peak period is scheduled from Monday to Saturday from 09.00-22.00 hrs. And Off Peak period from Monday to Saturday from 22.00-09.00 hrs. And on Sundays all day

From 1 October 2000, the government announced New tariff structure And have set the tariff for the OU to have more off-peak period, ie increase on Saturday And public holidays (Except holiday) all day, and set as the selection rate For the same electricity user But is a mandatory rate For power users Specific business (Hotel business) and new electricity users That uses electricity from 250,000 units per month or more Or use electricity more than 1,000 kW or more

TOU Rate

The rate of electricity collection that depends on the usage period Which is divided into 2 phases:

  • On Peak From Monday - Friday, 09.00-22.00 hrs.
  • Off Peak From Monday to Friday, 22.00-09.00 hrs.
  • And Saturday-Sunday National holiday (Excluding holiday compensation) All day

How to get benefit from TOU

TOU rate can save electricity cost When having good and appropriate electricity management such as

  • Avoid using the device. Or machines Which causes peak demand in the On Peak period (09.00-22.00 hrs.) To reduce the demand charge
  • In the event that the business has a 2-shift operation, consider 1 production shift to be in the Off Peak period (22.00-09.00 hrs.) In order to reduce the demand for electricity during the On Peak period, which has an Energy Charge. During Off Peak will be cheaper than the range of On Peak more than 55%
  • Work on Saturdays, Sundays and public holidays in full instead of regular work days Due to the said date No need to pay for electricity. And electrical energy bills Will be cheaper than the normal day during the On Peak of over 65%

In addition, entrepreneurs should consider Adoption of technology In the proper energy saving used together To increase electricity efficiency


Q&A with Solartron


Q: In the part of installing the solar roof for the office The biggest set is 25 kw, right?

A: Can be installed in many sizes Depending on the load profile of the customer, how much electricity they use Which can be designed to suit the electricity usage of customers Can be installed in various sizes from size 5, 10, 20, 25 kW to 1,000 kWp or 1MW

Q: Want to know the approximate area per 10 kw?

A: 100 sq.m. (can use approximately 10 sq.m. per kilowatt)

Q: If I have an area of about 150-200 sqm, how many kw should be installed and all installation fees How much is it?

A: If the area is a deck, there is no shadow to cover 15 - 20 kWp, but if it is a gable roof, it must be viewed again. Whether the direction is appropriate or not By choosing the main roof in the south is the best The roof is tilted about 5-20 degrees. The best, 1 kWp, can use the area of about 10 sq.m. per kilowatt. So, how much space to install is divided by 10 sq.m. And know how many kilowatts can be installed

Q: How much should the installation area be?


  • In the case of the roof installation area as a deck Or concrete floor can be installed without worrying
  • In the case of the roof that will be installed as a metal sheet Or tiles or whatever is the purlin structure In order to calculate if the construction is not yet started Or if built, calculate whether or not to support the weight or not

Q: What is the tax benefit?

A: Currently no, Maybe get the relevant BOI rights but must be on the BOI list provide support

Q: Regarding the finance, solartron has a financial sector partner? Is it easy to contact for credit? The way I normally use is the SCB and in the leasing I normally use is Thai Orix?

A: We have a guide to customers in Leasing. At present, besides 2 of the above, there are also Kbank, but Bank will consider the credit of that individual for customer