Solar Panels?

[nelsonic]

Final tasks as of Dec-2019

• Fixing snags Solar Panels? #20 (comment)
• Final EDP paperwork [dependency on Install BTE and increase electrical power  #70 being completed]
• Get application hooked up for solar panels [dependency on having the internet working]
• DAPE to finish configuration of equipment remotely

Context

home is based in a city centre with good infrastructure. 🌇 https://en.wikipedia.org/wiki/Braga
We have access to the National Grid which provides a reliable/consistent supply.
We don't need to tie up capital on Solar Panels and storage (batteries) up-front
because there is no shortage of electricity in the Portugal - many other countries have regular/prolonged power cuts ... e.g Eskom's "planned blackouts" in South Africa: 🌍🔌🚫😕
https://www.bbc.com/news/av/world-africa-31126033/south-africa-faces-power-crisis-and-blackouts

Portugal Renewable Energy Facts 🌬

Investment in renewable energy, specifically wind has been relentless!
In the 10 years from 2003 to 2013 wind generation capacity grew from 0.3GW to 4.73GW; 16x!

But the generation capacity does not even tell the "full story", the (annual) electricity generated by wind is even more impressive: from 0.48TWh to 12,19TWh; 25x!!

We will discuss the "grey area" (fossil fuels) below, these graphs are to contextualise the headlines.
The thicker grey line indicating consumption is significant; it shows the point (in 2015) when Portugal became a Net Exporter of Electricity.
For all the stats/metrics and ratios of consumption, export and efficiency, see:
https://tradingeconomics.com/portugal/energy-imports-net-percent-of-energy-use-wb-data.html

Headlines?

There is no shortage of headlines stating that Portugal generated over 100% of energy demand from renewables. e.g: Renewable energy generated 104% of Portugal's electricity consumption in March
https://www.independent.co.uk/news/world/europe/portugal-renewable-energy-generated-electricity-consumption-march-greenhouse-gas-environment-a8289656.html

But this headline is deeply misleading. (bordering on "fake news"...)

Actual Energy Production:

The annual breakdown of energy production is far less than 100%:
https://www.apren.pt/contents/publicationsreportcarditems/12-renewable-electricity-in-portugal.pdf

• https://www.ren.pt/pt-PT/quem_somos/facts_and_figures/
• https://www.apren.pt/en/renewable-energies/production
• http://www.ren21.net/wp-content/uploads/2018/06/17-8652_GSR2018_FullReport_web_final_.pdf

Current Data

The latest energy consumption stats are available online: https://www.ren.pt/en-GB
for September 2018 only 33.8% of energy consumed was from renewable sources:

https://en.wikipedia.org/wiki/Renewable_energy_in_Portugal

Solar?

Solar Panels have always been high on our list of features that are (very) "nice to have". ☀️🔋
We budgeted for Solar in our original plan: /dwyl/phase-two/braga#financials
And if we can get a good quote (including installation) from reputable supplier, we will go for it!

Having Solar is not a "blocker" to opening the house so have not been a focus;
We don't need to be "energy independent" or spend €40k on panels, inverters and batteries for "MVP".

We have "planned ahead" when doing the electrical re-wiring of the house and the cables are all in place to get the solar energy from the roof to the basement next to the mains consumer unit (where inverters, charge controller and batteries will "live").
When the time comes to install the panels and supporting equipment, we expect minimal "disruption" to the house for scaffolding on the north wall and installation should be complete within a couple of weeks.

Todo

• Prepare Roof (Drone) Video to send to suppliers with RFP (detailed context of our requirements)
• Prepare RFP to send to suppliers.
  • Surface Area in m²
  • Sun Exposure estimate
• Send RFP emails
  • Follow up with phone call 2 hours after sending email.
• Get Quote for Tesla PowerWalls

Solar Panel Suppliers (in Portugal) ☀️ 🇵🇹

Our research indicates that Damia Solar are the best value suppliers in PT:
https://www.damiasolar.com/produtos/kit_energia_solar/kit-de-autoconsumo-solar-4000w-de-injec-o-zero_da1002_112

Most of the kits available include OPZS Batteries https://en.wikipedia.org/wiki/Opzs
this is a Lead Acid battery generally composed of diluted sulfuric acid https://en.wikipedia.org/wiki/Sulfuric_acid ... I think we will give it a miss.

Is Solar Worth It?

On purely economic terms, solar energy is a poor use of capital. 💸
The best-case scenario "pay back period" for an investment in panels is 8 years.
The reality is more like 12 years without government incentives.
Even if we assume near-perfect panel positioning we can only expect around 5 hours
of sunlight (on average) per day.

Average Sunshine Per Day

Thankfully there is decent historical data freely available online for sunshine hours:

https://www.worldweatheronline.com/braga-weather-averages/braga/pt.aspx

The lowest sunshine recorded (in the available data) is 147 hours (averaged over Jan - March)

Drilling down into the data we see that the lowest sunshine was January 2016 with 94.5h.

We need to account for this and plan to source our energy from the National Grid in January each year.

There are two reasons for this dip: seasonal variation in angle of incidence of solar rays
and fewer days in the denominator. i.e. February typically has 28 days.

A reality check on renewables - David MacKay

This TED-Ed talk gives a good overview of the arithmetic for energy generation:

https://youtu.be/E0W1ZZYIV8o

Relevant Reading

A book I have found particularly useful in understanding solar is:
https://www.amazon.co.uk/Solar-Electricity-Handbook-Installing-Photovoltaic/dp/1907670688

If you don't have the time to read a 186 page book, there are a few good sites you can look at:

• Basic Solar Math: https://livingonsolarpower.wordpress.com/2013/03/23/basic-solar-energy-math/
• Solar energy generated m²: https://www.quora.com/How-much-solar-energy-is-generated-per-square-metre
• Solar Payback Period: https://news.energysage.com/understanding-your-solar-panel-payback-period note: this calculation assumes government financial "incentives"; we have none.
• Renewable Energy in Portugal:
  http://solar-algarve.com/welcome-to-solar-algarve-for-solar-energy-solutions/grid-connected-feed-in-tariffs/

Related Background Reading and General Knowledge

• Warren Buffet doesn't want you to have solar panels: https://www.fool.com/investing/2016/08/24/why-warren-buffett-wants-keep-solar-panels-off-you.aspx

#helpwanted

If anyone has experience of installing domestic solar panels
and has any advice/wisdom to share, please comment below!

[nelsonic]

The above graphs are for Electricity usage. If we look at Total Primary Energy Supply (TPES), the story is even more skewed toward hydrocarbons!
https://www.iea.org/publications/freepublications/publication/Energy_Policies_of_IEA_Countries_Portugal_2016_Review.pdf

Portugal relative to other IEA member countries in 2014.

Also relevant: https://en.wikipedia.org/wiki/Pumped-storage_hydroelectricity
(energy storage capacity is not expanding at the rate of renewable supply ...)

[nelsonic]

Consider adding ERoEI calculation to explain solar panels from a environmental perspective:
https://en.wikipedia.org/wiki/Energy_returned_on_energy_invested

[nelsonic]

Companies to request solar panel + installation quotes from:

• Damaia: https://www.damiasolar.com/produtos/kit_energia_solar/kit-de-autoconsumo-solar-4000w-de-injec-o-zero_da1002_112
• https://www.merkasol.com
• FF Solar: http://www.ffsolar.com/index.php?lang=PT&page=produtos&content=model&field=1&category=45&family=241
• Solar Full: https://www.olx.pt/anuncio/kit-5-000w-habitao-painel-solar-fotovoltaico-pico-10kw-prod-2750w-IDCdyaa.html

[nelsonic]

Through research, we note that the SunPower® X-Series Residential Solar appear to be the best panels. see: https://us.sunpower.com/sites/sunpower/files/sunpower-x-series-residential-solar-panels-x21-335-blk-x21-345-datasheet-504828-revg.pdf

https://www.ebay.co.uk/itm/4kw-SUNPOWER-X21-335W-Black-Solar-PV-System-THE-WORLDS-MOST-EFFICIENT-PANEL/132884779246

£5,995 for 12 panels (4kW) is definitely not "cheap"!
But if our objective is to maximise the amount of energy we can generate from the available space,
then we should only be considering panels that have this level of efficient conversion.

[nelsonic]

In addition to roughly 30 PV solar panels, we have 5 Solar Water Heating Panels planned.
We need to make the difference clear to people ... https://en.wikipedia.org/wiki/Solar_water_heating

[nelsonic]

Sketchup Layout of Solar Panels:

Pink = windows
Green = heat pump solar panels

[nelsonic]

@iteles we need to ask the suppliers of our solar panels what the price of the higher output panels are.

For reference, the SunPower X1 335W panels I linked to above (£5,995 for 12 panels) cost €620 each from Portuguese importer/installer "FF Solar" see: http://www.ffsolar.com/index.php?lang=PT&page=produtos&content=model&field=1&category=1&family=3

http://www.ffsolar.com/products/FF_lista_PVP.pdf

I think that sadly, the SunPower X1 are cost-prohibitive considering they have only 10% more output than a much more affordable 300W panel which costs around €160 ...

My original estimate in the April 2017 Biz Plan was €40k for panels and storage.
It's looking like with the recent price reductions that we might be able to get our complete solar system for €20k (with installation!) so that would be awesome! (the first underspend on the project!) 😮

[nelsonic]

@iteles I exported the Roof Dimensions with Windows and Suggested Solar Panel positioning as PDF:
braga-telhado-janelas-e-paineis-solares.pdf

This should be easier for Carlos (Solar Panel Engineer) to view. 🔍
(Please reply to his email with this as an attachment, thanks!) 📎

[iteles]

We met with solar panel providers at home this morning and discussed the positioning of the solar panels and required wiring.

The salient points from this meeting were:

• The panels can only be added to two of the sides of the roof
  • This is because all of the solar panels in one array must have a similar level of exposure to sunlight - i.e. the same angle and face the same way
• There must be a minimum of 10 solar panels (of the ones that have been proposed) wired in series, so we could not 'make use' of the space we would currently have left on the right hand side of the roof if we were to keep the heat pump solar panels there (green in the drawing above)
• The wiring will need to go down to where the inverter and batteries will be and also to the main electricity box
  • We have put in place a plan for this and it will have to be completed before the rest of the flooring goes down

Open questions

• Would it be more advantageous to use the prime sun location (right hand side of the roof drawing above) for additional photovoltaic panels instead of the heat pump panels?
  • For this, we need to know the Seasonal Coefficient of Performance (SCOP) of the heat pumps (I have emailed to request this and they came back with the COP of the solar panels, so I have replied to explain this is not what we need)
• Budget for higher capacity solar panels (330kW or 360kw) with the same surface area

[iteles]

🤦‍♀️ I had already started writing the above and the issue only updated with your latest comments when I submitted it @nelsonic

That'll teach me for getting distracted with emailing people part-way through a comment!

I had already emailed them both the drawing and the request for the updated quote 👍

[nelsonic]

The cost of Photovoltaic solar has decreased by 18% in the last year ... 😮
https://about.bnef.com/blog/battery-powers-latest-plunge-costs-threatens-coal-gas/

[iteles]

Chased today for the SCOP (to know whether we will need to by law have solar panels for the heat pumps specifically) and also for the spec of the solar panels for the heat pumps.

[iteles]

Have been chasing constantly but no joy.

In the meantime, now that we have a date for the roof #35, I've emailed the photovoltaics guys to see what we need to decide/put in place ahead of this getting done.

[iteles]

The latest proposals/costs for the solar panels include something interesting: solar panels on three portions of the roof. I have emailed them to query this.

All quotes are not for 315W panels.

They also include batteries for now - see note in #25 (comment) around costs for the decision to be made.

If only 2 sides on the roof:

[iteles]

@nelsonic These guys seem extremely knowledgeable and they're up the road if anything goes wrong. Do you think we should get a quote from the Póvoa de Lanhoso guys too or are you happy with these?

[nelsonic]

@iteles as you say, the supplier that has their HQ nearer to @home is preferable.
I don't think it would hurt to get a quote from the Povoa people to determine if they are competitive ... but from reading their marketing material last time we were there, their panels were more expensive ...

[iteles]

This has now been completely installed, both on the roof and hooked up to the electrical circuit (completely in early November 2019).
It should already be working, producing electricity that can be used in the house.

There are two steps missing here:

• Final paperwork for EDP: There needs to be paperwork submitted so that we can feed our extra electricity into the EDP network (the panels will be directed for home use first, then fill the batteries and only if there is spare electricity being produced will it be fed into the EDP network) - this can only be done after our electricity supply has been increased Install BTE and increase electrical power  #70
• Internet: Once we have the network up and running, they will come back and hook us up with the application so that we can see electricity production and flow.

[iteles]

We got our latest electricity bill which hadn’t changed and called them.

All the equipment is hooked up but apparently they haven’t started it yet because they require WiFi to ensure that the flow of energy is correct and everything working properly, particularly before our power is increased.

We agreed they would start everything up with a WiFi hotspot (obviously) and will let me know which day this will happen.

[nelsonic]

@iteles should we place the order with the ISP today so that we can get this ball moving?
The amount we are paying each month to EDP to run our dehumidifier almost outweighs the cost of broadband! And we are going to need a lot of electricity very soon to heat water which was the whole point of getting the solar panels ...

The conclusion of our research last year is still the same: MEO Fibra 1GB €38,99/mês (the fastest)
https://www.meo.pt/pacotes/fibra/outros-pacotes

Can I place the order today?

[iteles]

The question above was moved to #107.

The plan is for the solar panel folks to come today (20-Jan-2020) and get them up and running using a hotspot.

[nelsonic]

I'm here waiting for the Solar Panel people to arrive. ⏳
Hot spot indeed. Who is providing it? ❓
(as much as I want to donate my data to use the solar panels,
I'm 100% certain the software will require an update as soon as it connects to the net...) 🙄

[iteles]

Now that the internet has been hooked up, I've called the solar panel folks to come back and finalise the installation of the application. This is provisionally expected to be on Monday/Tuesday 27/28-Jan-2020.

[nelsonic]

Screenshot of Solax UI showing some lovely solar rays powering @home ☀️

[iteles]

We received confirmation on 3-Feb-2020, after some testing on our part, that there is a bug with the 'medidor' software so it is not measuring and therefore not dispensing the correct amount of energy to meet the (currently low) household needs.

Following up on this next week.

[nelsonic]

Indeed the solar output measurement software has a bug in it. Not very reassuring ... 🙄

[iteles]

@nelsonic The solar panel folks will be here this afternoon sometime after 15h00 to attempt to fix the issues.

[nelsonic]

@iteles thanks for following up. 👍 📆

[iteles]

Our solar panels have been working properly since late March 👍

We're now around the height of Summer:

(Those minimums are a joke, I wish it cooled down overnight but at 23h00 it's still 30 degrees out!)

And our outputs are looking pretty good!

Just after 11am:

And peak production around midday:

[iteles]

We have now agree to the new contract from EDP, so I am pulling together the information required by DAPE for them to finalize their configuration:

• CPE number
• NIF
• Potência contratada

[iteles]

This info has now been sent and they are putting in the request for the registration of the solar power system with EDP (as is mandated by law).
I have warned them that the new potência contratada #70 won't be in force until early September but they have said they want to put the request in now as it actually takes quite a long time.

@nelsonic They have also said that we need to have the 'contador' hooked up by law, which requires a SIM card with data capabilities to be installed in the GSM modem that is already installed downstairs.
Carlos mentioned they could provide this for €5 pcm but that most people prefer to get it through their existing providers as they get them at €2 or €2.50 pcm.

This is the first I remember hearing of this so I have requested the spec for the equipment:
Contador Itron ACE6000.pdf
Modem GSM ITRON.pdf

I suspect that this equipment is purely for the sale of electricity to EDP. If so, we will be spending more money on the data card every month than we'd get back in sales at this stage.
So I've asked the question on whether it's necessary and if so, how much data is required.

[nelsonic]

2 years later and Google Earth still thinks we have the old roof ... 🤷‍♂️

Need to dig out a drone photo. 📷

[iteles]

These have been working since. Issues to be opened on maintenance at this point I reckon!

[nelsonic]

@iteles Yeah I was thinking we could pass a pipe/hose with water from the Well #79 up to the roof through the caleira
and put a Tap 🚰 on the roof which we can then connect a hose to and spray (pressure wash) the panels periodically. 💭