Home PV Installations

Preamble

I received a cold-calling door-to-door salesman, Tariq, on a Saturday morning in September 2015. He was canvassing for names, for Solar Photovoltaic (PV) installations. He was from Apple Green Energy.  I agreed to be signed up… This led to a mad packed two weeks of surveys by different companies. Below is a list and the respective links to the various companies involved.

Surveys

See the blogs on

The final installation is documented in D-Day – The actual solar PV installation.

Video Tutorials

From mjlorton, an excellent tutorial, How to Solar Power Your Home #7 – Grid Tie v Micro Inverter v Power Optimizer v Charge Controller

From SolarEdgePV, the differences between traditional inverters, micro-inverters and SolarEdge system, SolarEdge technology overview

Again from SolarEdgePV, SolarEdge’s StorEdge(TM) Solution and Monitoring Portal

A lengthly SolarEdge training video

Additional Links

http://www.moneysavingexpert.com/utilities/free-solar-panels

http://www.totnesenergy.co.uk/index.php/solar-panels/solar-electricity/solar-panel-review

http://www.thegreenage.co.uk/optimmersion-links-solar-pv-and-the-immersion-heater/

http://www.immersun.co.uk/

Faux Gotchas

Lightning Protection

If some salesman tries to terrify you about lightning protection, fear not. To quote Steve West from Clear Sky Energy:

There seems to be two types of lightning that can cause damage to the components, direct & indirect.

If lightning were to directly strike, the modules & the optimisers have over-voltage protection fitted, although this would only limit the equipment damage and the only way to rule out lightning strikes on the modules would be to install lightning rods on the building.

Indirect lightning would be in the form of power surges coming up through the ground into the electrical system, the inverter has over-current protection built in on the AC & DC sides.

Maintenance Contracts

These consist of a chap coming every 6 months or year, with basically long pole window washers, using soft brushes and ionised water. For £160 a visit, it is cheaper to purchase a window cleaning system of your own.

Further quoted information from Steve West of Clear Sky Energy:

Maintenance on the system is generally very minimal as there is no moving parts, the panels are self cleaning and would only need a clean if they became heavily soiled with bird droppings but usually the sun bakes this and the rain washes it away, the inverter may need a dust off on the back where the cooling fins are from time to time, any issues on the system would become apparent on the monitoring portal, which would be flagged up.

We can offer a maintenance contract which would include an annual visit to carry out visual and electrical checks but generally this is more suited to bigger systems.

We would advise that the system is checked periodically, around every 3 – 5 years just to make sure the system is in good condition.

Optimiser/Inverter bottlenecks

Other suppliers may try to put the fear of god into you by saying that your chosen supplier has chosen the wrong combination of panels/optimisers/inverter. For example, the efficiency of the panels is too low, the rating of the optimiser/inverter is not sufficient to handle the power supplied by the panels, i.e. the SolarEdge optimiser should be the P405 and not the “cheaper”/”out-of-date”/”redundant” P300, or the inverter should be a SE4000 and not the SE3680.

However, when you examine their proposals you will see that they are offering the same ratings and/or models that they have just disparaged, and that the components are perfectly matched, throughout the proposed system, for the power generated.

Let’s be honest… It doesn’t matter what models you employ, or how recently they have been released, in the following year something better and more efficient will come along, as the rate, at which the technology is evolving, is exponential.

“Battery-Ready”

Some suppliers will offer battery ready systems (as compared to a “Basic” system). However… An example is the GroWatt tracker system, or Solar Storage System, where the tracker is part of the inverter. However this only works on one string (see the SolarEdge technology overview video above). It comes down to the Maximum Power Point Tracker (MPPT) which  is an electronic DC to DC converter that optimizes the match between the solar array (PV panels), and the battery bank or utility grid.  So for example, it would require two MPPT in a string inverter – or one with two tracking ports, if your system is  split over different facing roof surfaces. Such a system will NOT work in conjunction with a SolarEdge system of optimisers and inverter (for reasons explained in the video above).

SolarEdge are unveiling a battery read system today (13/10/2015) at NEC, which will work with the SE optimisers and inverter.

What is worth bearing in mind is the cost (and weight (50kg)) of the system. The price of Lithium has just gone up, the systems are guaranteed for 5 years and have an expected life span of only 10 years. It makes it quite unlikely that you will get your money back in the energy stored.  Until the price comes down, then they are probably not worth investing in.

Energy monitoring

Here is a list of possible brands/systems:

  • A system worth investigating is HIVE, for remote heating/energy management of your home;
  • LightWaveRF – not recommended
  • Z Wave – recommended
Advertisements

2 thoughts on “Home PV Installations”

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s