Monday 20 April 2015

Is This As Good as it Gets?

The Case for Good Looking Solar



Is that really the best you've got?


Do you like your coffee regular, large, super size or in a 6-litre bucket?  Americano, double espresso, flat, cappuccino?  Perhaps chocca-mocha or the icy one (whatever that’s called).  With skim milk, full fat or a drizzle of lard?  Do you want them to sprinkle brown dust onto the foamy topping for you?

Henry Ford famously said that you could have his Model T car “in any colour so long as it’s black”.  From the vantage point of our highly developed consumer market how amusing it is to imagine giving customers such limited choice.

Well, dear solar industry reader, why not take a fresh look at what are we offering our customers.

“You can have any solar installation so long as the panels are 2m x 1m modules fixed onto a rack above the roof, the array size matches a standard kit from a merchant and the panels are arranged in a nice easy rectangular shape.”

Yes, we talk about black-on-black modules or silver frames, poly or mono, micro inverters, optimisers or string inverters and all the rest, but are these technical issues really of interest to any but the earliest of early adopters?

Your home is your single biggest purchase and the roof is a very visible part of its kerb appeal.  If, when you come to sell it, a proportion of your potential buyers are put off by an insensitive solar installation on the roof it could cost you a lot of money.

Image: Viridian Solar Clearline PV30 and PV15 roof integrated solar panels


Forward thinking solar installation companies are already positioning themselves for a ‘post Henry Ford’ solar market.  They realise that as we move past early adopters chasing lucrative Feed in Tariffs and on to convincing the early majority to go solar we need to listen to people’s needs and offer them more choice, for example

Downsizing the installation to avoid over-crowding the roof
Grouping panels to create a more balanced, symmetrical installation
Roof integrated systems where panels look more intended and less like an afterthought
Large format modules for less clutter on the roof
Solar tiles and slates
Complete solar roofs
Offering solar thermal for roofs with limited space

As the costs of the equipment for solar installations have fallen, the extra cost of roof integration has fallen to the point where it can no longer be ignored as an option for customers.


But  the industry needs to overcome some prejudices.

First, on ease of installation.

Removing a patch of tiles adds very little extra work.  This is especially true for large format concrete interlocking tiles, which are quickly lifted.  Integrated solar panels are not just for new build.

Second, on maintenance.

A PV system should last more than 20 or 30 years so the chance is high that some maintenance of a roof covering will be necessary.  Even new homes may suffer a single cracked tile from a manufacturing defect or mishandling during roofing.

Replacing a broken tile is a simple and easy job for a roofing contractor working from a roof ladder.  If the cracked tile is behind a solar array, then it’s a very different situation.  Scaffolding is required, an electrician is needed to disconnect the solar and then remove panels to hunt for the source of the leak below.  A simple job costing £100 has become a costly exercise that could comfortably exceed £1000.  Looked at this way, roof integrated systems are preferable.

Third, on energy performance.

Everyone knows that integrated systems are going to run hotter than systems that have more open to ventilation, but how big is the actual effect on energy yield?  Viridian Solar recently published research on this subject in collaboration with the University of Cambridge Department of Engineering.  The answer turns out to be only 3%.

A new, sophisticated and more demanding breed of customers is emerging for the solar industry.  Less interested in details of the technology and less accepting of “one-size-fits-all” solutions.

More and more solar installation companies are seeking to escape the race to the bottom by differentiating their offer.  Building integrated solar panels are a way to broaden the appeal of solar to more customers and add value to your business.


This article first appeared in Solar Business Focus UK Magazine



Monday 6 April 2015

Solar Power in the CRC Energy Efficiency Scheme



The solarblogger spoke at a recent Solar Trade Association event on the commercial solar market.  In my presentation I discussed two drivers that were encouraging commercial customers to install solar power on their rooftops.

The first case study highlighted the importance of local planning requirements.  Many local authorities require that a percentage of energy consumption in new commercial buildings should come from renewable energy.  The calculation of the energy consumption of the building is woefully low because it doesn’t take into account heating or lighting in warehouse spaces or the use of the building.  However, the very fact of the planning requirement created the opportunity for the new warehouse owner to find out about the financial benefits of installing a solar PV system.  In the end they opted to install a system more than ten times larger than that required to discharge the planning requirement.

However, it was my second case study which raised an issue that this blog will clarify.

This case study was a company that operates a business and leisure park.  They have a very high annual power use of 5,500 MWh and an energy bill over £600,000 per year.

Any business with a combined electricity consumption across all sites and subsidiaries greater than 6,000 MWh per year must join the CRC scheme.

Once on the scheme, the business needs to inform government of details of all energy consumption - electricity and gas (where this is used for heating purposes).  A carbon emission level for consumed energy is calculated and the business must pay a carbon tax for every tonne it emits each year.

For 2014-15, the emissions factor for grid electricity is 0.5331 kgCO2/MWh.  The fees in this year were around £16/tonne depending on when you buy your allowances.

So any business breaching the 6,000MWh limit and qualifying for the scheme is hit with a bill for

6,000,000 kWh x 0.5331 x £16 / 1,000 =  £50,000

The asymmetric nature of the tax creates an enormous incentive for businesses that are approaching the cut off to reduce their use of energy.

A member of the audience questioned whether solar electricity counted towards energy use or not:

"We've been advised that because it's an efficiency scheme you have to total up all your electricity use, whether that comes from on-site solar panels, a diesel generator or grid electricity."

Further research has clarified the situation.  PV generated electricity should be reported, but is excluded from the CRC so long as the installation is eligible for, but has never received, Feed in Tariff (FITs) or Renewables Obligation (RO) payments.

See page 40, section 4.3.2 of The CRC Energy Efficiency Scheme guidance for participants in phase 2, version 2.  November 2014.

So there you have it.  An on-site PV solar installation is a valuable way for businesses that are approaching the CRC qualification limit to avoid the significant costs and administrative burden that come from having to join the scheme.

For businesses already on the CRC, the carbon tax rate of £16 a tonne translates into a saving of just under 1p for every kWh of electricity the PV offsets (to which you can add savings of around 10p of grid electricity not bought).  With the Feed in Tariff yielding 10p/kWh currently, to which can be added payments for export and savings on grid electricity, it seems like most businesses already on the CRC scheme would opt to take the FIT unless the PV installation could drive them below the qualifying limit for the scheme.