Guides
Help and Advice Guides – Getting Started
Ready for some reading?
Grab a cup of tea and take 20–30 minutes to get a clear understanding of solar and how it all works. With so much conflicting information out there, this guide is designed to cut through it and explain things properly — no jargon, just straight answers.
Written by Mike, business owner, qualified electrician for 20 years and solar PV engineer, these guides cover solar, batteries, EV chargers and heat pumps so you know exactly what to expect before getting a quote.
Whether you choose Spectra or go elsewhere, the aim is simple — better designed, better installed systems across the board. We know we won’t win every job, and that’s fine. Healthy competition pushes everyone to be better, and as long as systems are installed to the right standard, that’s a win for the industry as a whole. These guides are here to help you understand how it all works — and how it should be done.
Introduction
When looking at solar, one of the key decisions is:
Do you go in-roof or on-roof?
Both systems generate electricity in exactly the same way.
The difference is how they are installed onto your roof.
This guide explains:
- the real differences
- pros and cons of each
- which one actually makes sense
An on-roof system is the most common type of installation.
- Panels are mounted on top of your existing roof tiles
- Fixed using rails and brackets
- Sits slightly above the roof surface
This is the standard approach for most domestic and commercial installs.
A well-installed on-roof system depends heavily on the mounting system used.
At Spectra Solar, we use premium mounting systems from Renusol, designed for durability and long-term performance.
For more delicate roof types such as:
- slate roofs
- rosemary tiles
we incorporate the Genius Roof System.
This system:
- avoids unnecessary damage to tiles
- provides a more secure and weatherproof fixing method
- is specifically designed for these roof types
This is widely considered the best method of installation for slate and rosemary roofs, where standard mounting methods can be less suitable.
An in-roof system (also called integrated solar):
- Panels replace a section of your roof tiles
- Sit flush with the roof
- Become part of the roof structure
Instead of sitting on top, they are built into the roof itself.
A common example of an in-roof system is the GSE In-Roof System.
This system:
- integrates panels directly into the roof
- uses a flashing system to maintain weatherproofing
- is designed specifically for residential properties
GSE requires installers to complete specific training and accreditation before they can install their systems and offer the manufacturer’s warranty.
Spectra Solar is fully accredited with GSE, having completed their training and approval process.
This ensures installations are carried out to the required standard and qualify for warranty cover.
This is the biggest deciding factor.
In-roof:
- Flush with the roof
- Clean, modern look
- Less visible
On-roof:
- Sits above the roof
- More noticeable
- More “add-on” appearance
If aesthetics matter, in-roof usually wins.
On-roof systems generally perform slightly better.
Reason:
- There is a gap behind the panels
- Air flows underneath
- Panels stay cooler
In-roof systems:
- Sit directly in the roof
- Have less airflow
- Run slightly hotter
This can result in:
- slightly lower efficiency in some cases
Not a huge difference, but it is real.
On-roof:
- cheaper to install
- less labour
- no roof modification
In-roof:
- more expensive
- more labour
- involves altering the roof
In-roof systems are typically chosen for appearance rather than cost savings.
On-Roof – Best For:
- existing properties
- quick installations
- lower cost
This is why most installs are on-roof.
In-Roof – Best For:
- new builds
- re-roofing projects
- extensions
Because:
- you are already working on the roof
- tiles are being replaced anyway
In these cases, the cost difference can be reduced.
On-roof:
- easier to access
- simpler to replace panels
- quicker maintenance
In-roof:
- more integrated
- can be more involved if access is required
With in-roof systems, installation quality is critical.
Because:
- the system replaces part of the roof
- weatherproofing relies on correct installation
Using accredited systems like GSE and trained installers ensures:
- proper sealing and flashing
- long-term reliability
- valid manufacturer warranties
For on-roof systems, using the correct mounting system (such as Renusol or specialist slate systems) ensures:
- minimal roof disruption
- secure fixing
- long-term performance
“In-roof is better because it looks better”
Only partially true.
- looks better → yes
- performs better → no
“On-roof looks bad”
Not anymore.
Modern installs:
- sit closer to the roof
- use all-black panels
- look far cleaner than older systems
“In-roof is always worth the extra cost”
Not always.
It mainly makes sense when:
- appearance is a priority
- or the roof is being replaced
- Domestic retrofits → On-roof
- New builds / renovations → In-roof
- Commercial → Almost always on-roof
The difference comes down to:
- On-roof → better performance, lower cost, easier install
- In-roof → better appearance, higher cost, slightly lower performance
Most of the time:
On-roof is the more practical and cost-effective option
In-roof is usually chosen for:
appearance or when the roof is already being replaced
Next Step
Not sure which option suits your property?
- Request a quote for both options
- Or visit our showroom to see the difference in person
Not sure which option suits your property?
- Request a quote for both options
- Or visit our showroom to see the difference in person
Introduction
One of the most common questions when choosing solar panels is:
Should I go for all-black panels or standard panels?
At first glance, it looks like just a cosmetic choice.
In reality, there are small differences in appearance, performance, and cost.
To explain this properly, we will use a real example:
The Aiko 475W Neostar 3S Gen 3 All Black Panel.
Introduction
One of the most common questions when choosing solar panels is:
Should I go for all-black panels or standard panels?
At first glance, it looks like just a cosmetic choice.
In reality, there are small differences in appearance, performance, and cost.
To explain this properly, we will use a real example:
The Aiko 475W Neostar 3S Gen 3 All Black Panel.
Standard panels typically have:
- Blue-toned cells
- Visible grid lines (busbars)
- Silver or black frame
They are more traditional in appearance and you can clearly see the cell structure.
This is where the biggest difference lies.
All-black panels (e.g. Aiko 475W Gen 3):
- Clean, uniform finish
- No visible grid lines
- Blend into dark roofs
- Premium look
Standard panels:
- More contrast
- Visible cell pattern
- Slightly more “industrial” appearance
For most homeowners, this alone is enough to decide.
There is very little difference in real-world performance.
Using a modern panel like the Aiko:
- High efficiency (~23.8%)
- Advanced cell technology (N-type ABC) (TradeSparky)
However:
- All-black panels can run slightly hotter
- Heat slightly reduces efficiency
This means:
- Standard panels can be marginally more efficient in theory
In practice:
- the difference is negligible
- system design matters far more
Typically:
- All-black panels → slightly more expensive
- Standard panels → slightly cheaper
With higher-end panels like Aiko:
- you are paying for both aesthetics and top-end efficiency
The difference is usually:
- a few hundred pounds across a full system
- not a major deciding factor for most installs
Older advice used to be:
“All-black panels look better but perform worse”
That is now outdated.
Panels like the Aiko Gen 3:
- remove visible busbars
- increase active surface area
- maintain very high efficiency
Meaning:
- you get both appearance and performance
Choose All-Black Panels If:
- Appearance matters
- Panels are visible from the front of the property
- You want a cleaner, more modern look
- You are investing long-term
Choose Standard Panels If:
- Cost is the main priority
- Panels are not visible
- You want maximum output per pound
No — not in any meaningful way.
What actually matters:
- system size
- inverter setup
- panel placement
- shading
Panel colour is a minor factor.
“All-black panels are better”
They are better visually, not necessarily technically.
Modern panels like Aiko close the gap significantly.
“Standard panels are outdated”
Incorrect.
They:
• still perform very well
• are widely used
• offer strong value
Domestic installs:
- Majority choose all-black panels
- Driven by appearance
Commercial installs:
- Standard panels more common
- Focus on cost and return
The difference between all-black and standard panels is mainly appearance, not performance.
With modern panels like the Aiko 475W Gen 3:
- you no longer need to compromise
- you can have both high performance and a clean look
The difference comes down to:
- On-roof → better performance, lower cost, easier install
- In-roof → better appearance, higher cost, slightly lower performance
Most of the time:
On-roof is the more practical and cost-effective option
In-roof is usually chosen for:
appearance or when the roof is already being replaced
Introduction
This is the first question most people ask:
Are solar panels actually worth it in the UK?
Short answer: yes — but only if the system is designed and installed properly.
This guide breaks down:
- how solar saves you money
- what affects the return
- what most people get wrong
Solar panels generate electricity during the day. That electricity is used by your home first.
This means:
- You buy less electricity from the grid
- Your bills go down
Any unused electricity is exported back to the grid, and you get paid for it through the Smart Export Guarantee (SEG).
There are three main factors:
- How Much Electricity You Use
The more electricity you use, the more you can save.
Typical examples:
- Low usage → slower payback
- High usage → faster payback
- How Much You Use During the Day
Solar generates in daylight hours.
If you are home during the day (or have things running like):
- appliances
- home office
- air conditioning
you will use more of your own electricity → higher savings.
- System Design
This is where most installs go wrong.
A good system:
- matches your usage
- uses the right inverter setup
- avoids oversizing or undersizing
A poor system:
- looks good on paper
- performs badly in reality
A standard UK home with a properly designed system can typically:
- Reduce electricity bills significantly
- Offset a large portion of daytime usage
- Generate additional income through export
Exact figures vary depending on:
- roof direction
- shading
- usage habits
- system size
Avoid anyone giving blanket “you’ll save £X” figures without understanding your usage.
Typical payback:
- 6–10 years for most domestic systems
After that:
- electricity generated is effectively free
- systems typically last 25+ years
Yes.
Common misconception:
“The UK isn’t sunny enough”
Reality:
- solar works on daylight, not heat
- panels still generate on cloudy days
- cooler temperatures can actually improve efficiency
You will generate less in winter than summer, but systems are designed with this in mind.
Choosing Based on Price Alone
Cheap systems are often:
- poorly designed
- badly installed
- lacking aftercare
- Oversizing the System
Bigger is not always better.
If you generate more than you can use:
- you export it cheaply
- you reduce your return
- Ignoring Battery Storage (or Misusing It)
Batteries can increase savings, but:
- not every home needs one
- oversizing batteries is common
- Choosing the Wrong Installer
This is the biggest risk.
The same equipment installed by:
- a good installer → performs well
- a poor installer → causes problems
Solar may be less suitable if:
- your roof is heavily shaded
- you have very low electricity usage
- your roof orientation is poor
Even then, it depends on the design — not just the property.
Solar panels are worth it in the UK when installed correctly and designed around your actual usage.
Most issues come from:
- poor system design
- incorrect sizing
- choosing the wrong installer
Get those right, and solar is a solid long-term investment.
Solar panels are worth it in the UK when installed correctly and designed around your actual usage.
Most issues come from:
- poor system design
- incorrect sizing
- choosing the wrong installer
Get those right, and solar is a solid long-term investment.
This is where most people struggle.
Do you go local?
Do you choose a big national company?
Do you trust a familiar name?
If you are new to solar, it can be difficult to know what actually matters.
Below are the key checks you should carry out before choosing an installer.
A term you will hear a lot is Microgeneration Certification Scheme (MCS).
MCS-certified installers have been assessed to meet specific standards and are authorised to issue MCS certificates for installations under 50kW.
This matters because:
- You need an MCS certificate to export electricity to the grid
- It is required to receive payments through the Smart Export Guarantee (SEG)
It is not possible for one company to “MCS certify” another company’s installation after the fact. If your installer is not MCS registered, you will not receive certification.
You can check if a company is registered here:
https://mcscertified.com/find-an-installer/
Installers must also be registered with a consumer code provider such as:
- HIES
- RECC
These schemes exist to protect you as the customer and allow installers to offer insurance-backed guarantees.
To be approved, companies must:
- Already be MCS certified
- Pass background checks
- Follow strict consumer protection rules
You can verify membership directly on their websites.
Your installer must also be registered with an electrical certification body such as:
- NAPIT
- NICEIC
These bodies allow installers to:
- Notify building control
- Certify electrical work legally
- Install systems such as solar, batteries, EV chargers and heat pumps
A quick member search on their websites will confirm what the company is actually approved to install.
Use Companies House to check:
- How long the company has been established
- Whether accounts are up to date
- Who the directors are
- The registered office address
Link:
https://find-and-update.company-information.service.gov.uk/
If a company is brand new or filing late accounts, that is a risk indicator.
Check where the company actually operates from.
- Is it a proper business premises?
- Is it just a registered address (e.g. accountant)?
- Are they working out of a house or garage?
If possible, visit them.
A company willing to show you:
- their premises
- their systems
- their setup
is far more transparent than one that avoids it.
Reviews matter, but they can be misleading.
Common platforms:
- Trustpilot
- Feefo
- Which? Trusted Traders
Be aware:
- Fake reviews are common
- Overly generic reviews are a red flag
- Repeated “name dropping” of staff can be staged
Better signs:
- Verified purchase reviews (e.g. Which?)
- Detailed reviews describing the actual job
- A mix of feedback (not just perfect scores)
Do not just look at the rating—read the content.
Most issues with solar installations come down to who installs it, not the equipment itself.
If you get the installer right:
- the system will be designed properly
- it will be installed correctly
- and it will perform as expected
If you get it wrong, problems usually follow.
Introduction
If you’ve looked into solar, EV chargers or heat pumps, you’ve probably come across the term DNO approval.
For most customers, it’s unclear:
- what a DNO is
- whether approval is needed
- and if it’s going to delay things
This guide explains it clearly so you know what to expect.
A DNO (Distribution Network Operator) is the company responsible for the electricity network in your area.
They manage:
- the cables in the street
- how much power your property can import
- and how much you can export back to the grid
Any system that:
- generates electricity (solar)
- or uses a large amount of electricity (EV chargers / heat pumps)
may need to be assessed by the DNO.
Solar systems export electricity back to the grid, so they fall under DNO rules.
What determines whether it is G98 or G99 is not the number of panels — it is the inverter size.
The inverter controls how much power can be exported and used within the property at any one time.
G98 – Smaller Systems
- Inverter size up to 3.68kW per phase
- Installed first, then notified afterwards
G99 – Larger Systems
- Inverter size above 3.68kW per phase
- Requires approval before installation
You can have:
- a large number of panels
- but a smaller inverter
and still fall under G98.
Or:
- a smaller system
- with a larger inverter
and require G99.
It’s the inverter output that matters — not the number of panels on the roof
When applying under G99, the DNO may:
- limit the inverter size
- restrict how much you can export to the grid
- request system changes to suit the local network
This can result in:
- capped export on larger systems
- adjustments to system design
Some DNOs may also:
- charge a fee for assessing larger systems (G99 applications)
In some cases, systems are deliberately kept within G98 limits so they can be installed quicker.
While this can simplify the process, it can also:
- limit performance
- reduce long-term generation
With larger inverters now widely available, it is more common to install higher-capacity systems where appropriate.
For example:
- properties with higher usage
- homes with EV chargers or heat pumps
There is little benefit in installing a small inverter (e.g. 3.68kW) in these cases, as:
- the property continues to draw from the grid
- solar generation is unnecessarily restricted
It is usually better to size the inverter correctly so grid usage is reduced as much as practically possible
Battery performance is directly linked to the inverter.
In most systems:
- the charge and discharge rate of the battery is limited by the inverter size
For example:
- a 3.68kW inverter will typically only allow around 3.68kW charge/discharge, even if the battery is capable of more
This means:
you cannot install a small inverter and expect to deliver higher power (e.g. 7kW) from the battery into the property
What This Means
- Larger inverters:
- allow more usable solar
- increase battery performance
- reduce reliance on the grid
- Smaller inverters:
- restrict output
- limit battery performance
- increase grid usage
EV chargers and heat pumps increase the electrical demand of a property.
Because of this:
- they may require DNO notification or approval
- and are often considered alongside solar in system design
This ensures:
- your supply can handle the load
- everything works together properly
EV chargers and heat pumps increase the electrical demand of a property.
Because of this:
- they may require DNO notification or approval
- and are often considered alongside solar in system design
This ensures:
- your supply can handle the load
- everything works together properly
No — not in any meaningful way.
What actually matters:
- system size
- inverter setup
- panel placement
- shading
Panel colour is a minor factor.
What This Means for You
Looped supplies can limit how much power your property can safely draw.
For higher-demand systems such as:
- EV chargers
- heat pumps
the DNO may require the supply to be de-looped (separated).
When Does De-Looping Happen?
De-looping is not always required before installation.
In many cases:
- systems can still be installed
- and the property is added to a list to be de-looped later
At the time of writing:
waiting times for de-looping can be over 12 months
This work is carried out by the DNO and is outside of the installer’s control.
What About Solar?
Solar on its own does not usually trigger de-looping, as it primarily exports power rather than increases demand.
However:
- it may still form part of the overall system assessment
- especially when combined with EV chargers or heat pumps
No.
We handle all DNO applications and communication on your behalf
DNO approval is a normal part of installing modern electrical systems.
Whether it’s:
- solar
- EV charging
- or heat pumps
everything needs to be designed to work properly with both your property and the local network
G99 approval is required before installation — not after
Any solar PV system with an inverter above 3.68kW per phase must receive DNO approval before the installation can take place.
Typical timescales:
- up to 45 working days
- depending on system size and complexity
This is a standard part of the process and is factored into the project timeline from the outset.
Introduction
One of the most common questions after looking into solar is:
Do I need a battery as well?
The honest answer is:
No — but in many cases, it can significantly improve how much you save.
This guide explains when a battery makes sense, when it doesn’t, and what most people get wrong.
Without a battery:
- Solar powers your home during the day
- Any unused energy is exported to the grid
With a battery:
- Excess solar energy is stored
- You can use it later (evening/night)
This increases how much of your own energy you use.
Electricity you use yourself is worth more than electricity you export.
- Import (what you pay) → high cost
- Export (what you’re paid) → lower value
A battery helps shift your usage so you rely less on the grid.
You’re Out During the Day
If no one is home:
- most solar gets exported
- savings are reduced
A battery stores that energy so you can use it later.
- You Use Most Electricity in the Evening
Typical pattern:
- low usage during the day
- high usage in the evening
A battery helps move your solar energy into the hours you actually need it.
- You Want More Control Over Your Energy
A battery gives you:
- more independence from the grid
- better use of your solar system
- more predictable energy costs
- You’re on (or Can Access) an Off-Peak Tariff
This is where batteries become significantly more effective.
You can:
- charge the battery overnight using cheaper off-peak electricity
- use that stored energy during the day when electricity is more expensive
This means your system is not just relying on solar—it is actively reducing your energy costs through tariff optimisation.
This is particularly useful:
- in winter when solar generation is lower
- for higher electricity users
- when combined with EV charging or electric heating
Some battery systems can provide power during a power cut.
However, this is not standard on all systems and usually requires additional equipment.
To enable backup functionality, systems typically need:
- a gateway or changeover switch to isolate the property from the grid
- a dedicated earth rod for safe operation during island mode
Without this setup:
- the system will shut down during a power cut (standard safety behaviour)
With the correct setup:
- selected circuits (or sometimes the whole property) can remain powered
This is useful for:
- essential appliances
- lighting
- maintaining power during outages
You Already Use Most of Your Solar
If you are home during the day and using electricity as it’s generated, you may already be getting good value without a battery.
- Commercial Properties (Common Scenario)
In many commercial settings, a battery may offer limited benefit.
Typical pattern:
- High electricity usage during the day
- Solar generation is used instantly on-site
- Very little excess energy available to store
In addition:
- Energy usage often drops significantly after 5pm
- This is when solar generation is already low or stopped
This means:
- there is little surplus energy to charge a battery
- and limited demand later in the day to use stored energy
In these cases, a battery may:
- add cost without delivering meaningful additional savings
- Lower Electricity Usage
Lower usage can mean:
- smaller savings
- longer payback
- Budget Constraints
Batteries increase upfront cost.
A common approach is:
- install solar first
- add a battery later
Most modern battery systems are modular.
This means:
- you do not need to install full capacity upfront
- additional battery units can be added later
Example:
- Start with ~5–6kWh
- Expand to 10kWh+ if needed
This allows your system to grow with:
- increased usage
- EV charging
- heat pumps or air conditioning
Battery installations in the UK must follow PAS 63100 guidance.
This standard sets out where batteries can safely be installed.
Typical considerations include:
- avoiding escape routes (e.g. hallways)
- restrictions on certain internal locations
- suitability of lofts and cupboards
- fire safety and ventilation requirements
Outdoor Installation (Common Approach)
Many modern battery systems are rated IP65, meaning they are suitable for outdoor installation.
In most cases:
- batteries are installed externally
- mounted on an outside wall
- positioned close to the inverter or supply
This is often the preferred option as it:
- avoids internal space restrictions
- simplifies compliance with safety guidance
- reduces disruption inside the property
Cold Weather & Battery Heaters
Some newer-generation batteries include built-in heaters.
These:
- allow the battery to operate more effectively in colder temperatures
- help maintain performance during winter
- are particularly useful for external installations
A competent installer will:
- select suitable equipment
- assess location
ensure full compliance and performance
Solar Only:
- Use solar during the day
- Export unused energy
- Import at night
Solar + Battery:
- Use solar during the day
- Store excess energy
- Use stored energy in the evening
- Charge overnight at cheaper off-peak rates if available
Oversizing the Battery
If the battery:
- never fills
- or never empties
you are not getting value from it.
- Assuming a Battery Eliminates Bills
It won’t.
You will still:
- import energy at times
- rely on the grid
- Ignoring Tariff Strategy
A battery without the right tariff:
- loses a large part of its value
Off-peak charging is a key part of making a battery system work properly.
Yes.
Two main options:
- Hybrid system → installed with solar
- AC-coupled battery → added later
Because most systems are modular, expansion is straightforward in many cases.
You do not need a battery for solar to work.
However, a battery can:
- increase your savings
- improve system performance
- give you more control over your energy
- provide backup power (with the correct setup)
Especially when combined with:
- solar generation
- off-peak overnight charging
The right setup depends on:
- your usage
- your tariff
- your budget
- your future plans
Not sure if a battery is right for your setup?
- Request a quote based on your usage
- Or use our system builder to see recommended options
Introduction
One of the most common questions is:
How many solar panels will I need for my home?
The honest answer is:
It depends on your electricity usage, not just your roof size.
This guide explains how system size is worked out and what actually matters.
This is the starting point.
You can find it on your electricity bill (measured in kWh per year).
Typical UK usage:
- Small household → 1,800–2,500 kWh
- Medium household → 2,500–4,000 kWh
- Large household → 4,000–6,000+ kWh
The higher your usage, the more panels you can justify.
Most modern panels are around 450W each.
Typical UK performance:
- 1 panel ≈ 350–400 kWh per year
So:
- 10 panels ≈ 3,500–4,000 kWh/year
- 12 panels ≈ 4,200–4,800 kWh/year
- 16 panels ≈ 5,600–6,400 kWh/year
This is why panel count is directly linked to usage.
There are two main approaches:
- Offset Your Usage
System sized to cover most of your annual consumption.
Example:
- Usage = 3,500 kWh
- System = ~10 panels
- Maximise Your Roof
Install as many panels as will fit.
This works if:
- you plan to add battery storage
- you expect usage to increase (air conditioning, heat pump)
A typical panel is about 1700mm Long x 1150mm Wide
Quick guide:
- 8 panels → ~14m²
- 10 panels → ~17m²
- 12 panels → ~20m²
- 16 panels → ~27m²
Other factors:
- roof shape
- obstacles (chimneys, vents)
- layout efficiency
A typical panel is about 1700mm Long x 1150mm Wide
Quick guide:
- 8 panels → ~14m²
- 10 panels → ~17m²
- 12 panels → ~20m²
- 16 panels → ~27m²
Other factors:
- roof shape
- obstacles (chimneys, vents)
- layout efficiency
This is where most estimates fall short.
Two houses with the same usage can need different systems depending on:
- when electricity is used
- whether someone is home during the day
- future additions (EV, battery, AC, heat pump)
Guessing Based on House Size
System size is based on usage, not property size.
- Oversizing Without a Plan
Too many panels without:
- battery storage
- increased usage
means exporting more at lower value.
- Undersizing to Save Money
Smaller systems:
- cost less upfront
- but reduce long-term savings
- 6–8 panels → small usage homes
- 10–12 panels → most standard homes
- 14–18 panels → high usage / future-proofing
The right number of solar panels depends on:
- your annual electricity usage
- your roof space
- your future plans
Not just what fits on the roof.
If you want an exact answer based on your property:
- Request a quote
- Or use our system builder to see recommended system sizes
Introduction
After “Are solar panels worth it?”, the next question is:
How much will I actually save?
The answer depends on how your system is used, not just how much it generates.
This guide explains where the savings come from and what affects them.
Introduction
After “Are solar panels worth it?”, the next question is:
How much will I actually save?
The answer depends on how your system is used, not just how much it generates.
This guide explains where the savings come from and what affects them.
For a standard UK home with a properly sized system:
- A large portion of daytime electricity use can be covered
- Electricity bills can be reduced significantly
- Additional income comes from exported energy
Exact savings vary depending on:
- electricity usage
- system size
- how much energy is used during the day
Avoid fixed “you’ll save £X” claims without proper assessment.
Daytime Usage
The more electricity you use while the system is generating, the more you save.
Examples that increase savings:
- Working from home
- Running appliances during the day
- Using air conditioning
- Charging devices and batteries
- System Size
- Too small → limited savings
- Too large → more export, lower return
Correct sizing is critical.
- Battery Storage
Batteries allow you to:
- store excess solar energy
- use it later (evening/night)
This increases how much of your own energy you use and can improve savings.
They can also be charged from the grid overnight on cheaper tariffs.
If you are on an off-peak tariff, you can:
- charge your battery overnight at a lower rate
- use that stored energy during the day when electricity is more expensive
This is particularly useful in winter when solar generation is lower and helps keep energy costs down year-round.
- Electricity Prices
The higher electricity prices go:
- the more valuable your solar becomes
This is why solar improves over time.
Modern energy tariffs often offer cheaper electricity overnight.
With the right setup, your battery can:
- charge overnight at a lower rate
- supply your home during peak daytime hours
This means your system is not just relying on solar—it is actively reducing costs using tariff optimisation.
This works especially well:
- in winter months
- for higher electricity users
- when combined with EV charging
Without solar:
- You buy all electricity from the grid
With solar and battery:
- You use solar during the day
- Store excess energy in your battery
- Use stored energy in the evening
- Optionally charge overnight at cheaper rates
The difference between these is your saving.
“I’ll eliminate my electricity bill”
Not usually.
You will still:
- use electricity at night
- import during low-generation periods
“Export payments are where the money is”
Incorrect.
- Export is a bonus
- Self-use is where the real savings come from
“Bigger system = more savings”
Not always.
If you cannot use the energy:
- you export more
- return drops
- Use appliances during the day where possible
- Consider battery storage (if suitable)
- Take advantage of cheaper overnight tariffs
- Size the system correctly
- Choose the right installer
Solar savings are driven by how much of your own electricity you use, not just how much you generate.
The best systems are designed around:
- your usage
- your lifestyle
- your future plans
Want to see what you could actually save?
- Request a quote based on your usage
- Or use our system builder for a tailored estimate
Introduction
Not all roofs are the same, and this directly affects how solar panels are installed.
Your roof type will influence:
- how the system is mounted
- how long installation takes
- overall cost and complexity
There is no one-size-fits-all approach.
The installation method should always match the roof type.
Concrete tile roofs are the most straightforward type for solar installations.
They are:
- strong
- widely used
- easy to work with
Installation Method
- On-roof mounting system
- Roof hooks fixed into rafters
- Rails installed above the tiles
- Panels mounted onto rails
A key part of a proper installation is notching the tiles.
Tile Notching (Important)
Tiles should be:
- carefully notched where the roof hook passes through
- refitted so they sit flat back in place
This:
- prevents tiles from lifting or rocking
- maintains proper weatherproofing
- reduces stress on the tile over time
This is now standard practice on quality installations.
There is no valid reason to leave tiles sitting proud:
tiles should always be notched so they sit correctly and maintain the integrity of the roof
Mounting System Quality
At Spectra Solar, we use premium mounting systems from Renusol.
Why We Use Renusol
- Long-established manufacturer with a proven track record
- High-quality materials and engineering
- Designed for long-term durability
From real on-site experience:
Some lower-cost mounting systems can:
- flex when being walked on
- feel unstable when accessing panels higher up
Renusol systems:
- remain rigid under load
- provide a solid working platform
- give greater confidence in long-term structural integrity
These systems typically cost more, however:
when installing a system designed to last 25–30+ years, it is not worth cutting costs on mounting equipment
Key Points
- Fast installation
- Cost-effective when done properly
- Minimal complications
- Tiles must be notched correctly
- Quality mounting systems are essential
Plain tile (rosemary) roofs are typically found on:
- older properties
- character homes
- traditional builds
These tiles are smaller and more delicate, so the installation method matters far more.
Installation Methods (Important)
There are multiple ways to install onto these roofs.
Older/traditional method:
- Redtip Roofhook (Hookstop)
This system was designed to:
- reduce stress on the tile
- prevent tiles cracking from bracket pressure
However, in practice it can:
- leave tiles sitting slightly proud
- affect how the tiles above sit
- result in a less uniform finish across the roof
Modern Method (Preferred)
- Genius Roof Solutions InterFlash system
At Spectra Solar, we use the Genius InterFlash system.
Why We Use InterFlash
- Cleaner, more integrated finish
- Tiles sit correctly and uniformly
- Less stress placed on surrounding tiles
- Improved weatherproofing
- More refined installation method
We were also one of the first companies to install using this method, and it has proven to be a better solution in practice.
InterFlash provides a more consistent and reliable finish compared to older hook-based methods
As with other premium systems:
- it typically costs more
- but delivers a significantly better long-term result
Key Points
- More time-intensive installation
- Requires higher skill level
- Finish and method matter significantly
- Not worth compromising to save cost
Slate roofs are:
- brittle
- expensive to repair
- easy to damage if handled incorrectly
They require a specialist approach, and the installation method is critical.
Installation Methods (Important)
Some systems install by:
- drilling through the slate
- fixing directly through the tile
This can:
- transfer load onto the slate
- create stress points within the material
Over time, due to:
- wind loading
- snow loading
- natural movement
this can lead to:
- cracked or broken slates
The issue is:
once the system is installed, these slates are extremely difficult to access without removing part of the solar array
This can result in costly and avoidable repairs.
Installation methods that involve drilling through slate in multiple locations—such as the Fastensol A-Slate—can increase the risk of long-term damage and are generally not recommended where better solutions exist.
Systems We Use
At Spectra Solar, we use:
- Genius SpeedFlash
This system:
- avoids transferring load onto the slate
- provides proper flashing and sealing
- improves long-term reliability
- reduces risk of future damage
Key Points
- Labour-intensive installation
- Higher cost compared to tile roofs
- System choice is critical
- Avoid invasive methods that stress the slate
Metal roofs are commonly found on:
- warehouses
- commercial units
- agricultural buildings
Types include:
- trapezoidal sheet
- standing seam
Installation Method
- Direct fixing to the roof structure
- Clamp or bracket systems depending on type
- No tile removal required
Key Points
- Very fast installation
- Highly efficient layout
- Ideal for large systems
This is one of the most efficient roof types for solar installations.
The type of roof you have affects:
- installation method
- system design
- cost
- long-term reliability
Using the correct system for each roof type is critical to:
- avoid damage
- maintain weatherproofing
- ensure long-term performance
- Concrete tile → simple, but must be installed properly (tiles notched, quality mounting used)
- Plain tile / rosemary → modern systems like InterFlash provide a far better finish than older hook methods
- Slate → system choice is critical; avoid invasive methods that place stress on the slate
- Metal → fastest and most efficient installs
If you are installing a system designed to last 25–30+ years, the mounting system matters just as much as the panels themselves.
Premium systems like Renusol and Genius may cost more, but it is not worth cutting costs — doing it properly from the start avoids far greater issues later.
Whoever you choose to install your system, make sure they are using high-quality mounting equipment.
Products from Renusol and Genius Roof Solutions are widely recognised as premium solutions within the industry.
Many companies will choose cheaper mounting systems to reduce upfront costs and appear more competitive.
However:
this is often a false economy for a system designed to last 25–30+ years
Using the right equipment:
- improves long-term reliability
- reduces risk of roof issues
- ensures the system performs as intended
Cutting costs on mounting may save money initially, but can lead to:
- poorer installation quality
- increased risk of failure
- higher costs over time
Not sure what roof type you have or what system is suitable?
- Request a quote
- Or speak to our team for advice based on your property
Introduction
One of the most common questions is:
“Will my current electrics be suitable for solar, EV charging, or a heat pump?”
In most cases, yes — but a proper installation often involves adding new electrical infrastructure rather than relying on what’s already there.
This guide explains what is typically required and what to expect.
Whether you are installing:
- solar
- an EV charger
- or a heat pump
each system needs a safe, compliant connection into your property.
Rather than modifying older setups, the correct approach is usually to:
install a new, dedicated electrical connection point for the system
This ensures everything is:
- safe
- compliant
- designed correctly from the start
In many cases, we install a new, separate fuse box for the system.
This is standard practice on quality installations.
Why a New Fuse Box Is Used
- Provides a dedicated supply
- Avoids overloading existing electrics
- Ensures compliance with current regulations
- Allows correct protection devices to be installed
A modern fuse box will typically include:
- surge protection
- correct isolation
- appropriate circuit protection
Why Not Just Use the Existing Fuse Box?
While sometimes possible, it is often not the best solution.
Older fuse boxes may:
- lack space
- not meet current standards
- require unnecessary modification
In many cases:
installing a new fuse box is cleaner, safer, and more future-proof
Your electricity meter and meter box are not owned by you — they are owned by the DNO (Distribution Network Operator).
Because of this:
- we do not install major electrical equipment inside the meter box
This includes:
- fuse boxes
- large electrical components
However, some essential connection components are installed within the meter box where required, such as:
- earth connections
- Henley Blocks
These are standard and required to safely connect new systems.
The meter box is used for connection purposes only and is not designed to house additional electrical systems. Any competent electrician or surveyor would avoid using this space for that purpose.
Correct earthing and bonding are critical for safety and are checked on every installation.
What We Check
- Earthing arrangement (TN-C-S, TN-S, etc.)
- Main protective bonding to incoming services
Bonding Requirements
Where metallic services are present, bonding must be in place.
This typically includes:
- gas pipes (if metallic)
- water pipes (if metallic)
In line with UK wiring regulations (BS 7671):
- these services must be bonded to the main earthing terminal
- bonding conductors must be correctly sized and installed
If bonding is:
- missing
- undersized
- or not compliant
it will need to be upgraded. This is typically additional work, but a simple check can confirm whether it is already present or required.
Cabling is installed using methods suited to the system and location.
- Cables are protected using plastic conduit where required
- For certain installations, EV Ultra Cable is used to combine power and data in a single run
This helps:
- keep installations neat
- reduce visible cabling
- improve the overall finish
For solar PV systems, circuit design is carried out correctly to avoid unnecessary issues such as nuisance tripping.
Main system components are installed either:
- internally, where suitable
- or in a separate external enclosure
External setups typically use:
- IP-rated enclosures
- purpose-built fuse boxes
This ensures:
- compliance
- safe access
- long-term durability
In many installations:
- a new fuse box is added
- bonding may need upgrading
- minor electrical improvements may be required
This is normal and part of doing the job properly
“It all has to go into my existing fuse box”
Not true.
A separate fuse box is often the correct approach.
“Everything goes in the meter box”
Incorrect.
The meter box is for connection only, not for housing additional electrical systems.
“This means major electrical work”
In reality:
- this is standard practice
- work is completed as part of the install
- it improves safety and reliability
Most properties are suitable for:
- solar
- EV charging
- heat pumps
However:
a proper installation will usually involve adding a new, modern electrical connection point and ensuring earthing, bonding, and protection methods are fully compliant
Not sure what your current setup is?
- Request a quote
- Or Speak to the team directly on 01942669601
