Random Renewables Thread

slave1

https://www.boards.ie/discussion/comment/120248475#Comment_120248475

4 times a year, 10minutes each time

unkel

https://www.boards.ie/discussion/comment/120248417#Comment_120248417

You will find the difference in generation will be minimal. Orientation is far more important than angle.

bullit_dodger

https://www.boards.ie/discussion/comment/120248563#Comment_120248563

Dunno about that. 8kWp of panels with 75 degree slope (optimized for Dec) will produce this for the year.

Adjusting that same 8kWp array to a 45deg slant (for summer time)

So 200kWhr more a month in May. If you were getting a FIT of that of €0.20/kWH......well you can do the math. :-)

To be fair, there's not a huge amount to be gained by optimizing it for "winter production" over the standard 38deg that most of us have as the "general fixed angle".....but if you DO optimize for winter, then you will hurt summer, and that's why it's important to consider adjustable angles.

unkel

You "forgot" that it works the other way around ;-)

I'd put it in for the max yearly output. So you would have zero benefit in May but a tiny loss in Dec and Jan. What, maybe 10kWh per month @8c (it competes with night rate if you have a big battery). So €0.80 per month. Would I really spend hundreds to have a tilting mechanism and then break my legs on an icy day in November to climb into the structure and change the angle for such a lousy saving? I would in me bollox 😂

Thanks for providing the data to prove my point though 🤣

bullit_dodger

It's not my imaginary array, it's ELM's :-) I mentioned it above, that there's a lot to be said for fixing it and be done with it (at 38deg). No, my point was always that if you do optimize for winter then you need to consider having a summer angle, or you'll wreck the production there needlessly.

That's a trade off that each person would have to make individually, if the marginal gains in winter would be worth the effort. I don't see it as a zero sum game where there's a right/wrong solution, but one that each owner would have to decide for themselves what's right for them.

I would personally be pretty confident you could come up with a secure cheap movable mechanism that would be easy to change without having to climb into the frame etc. Some sunny day in Oct to change it into "winter mode" and another sunny Saturday afternoon in March to swap it into summer mode - 10 minutes each way. But sure, differences of opinion are valid, Lot to be said for fixing and being done!

Thing is though is that those few extra meager kWhr in winter are ones which he needs the most.....isn't that the problem being solved?

slave1

No extra costs in a tilted array, instead of fixing support piece permanently to upright you drill a hole through for a nut and bolt in a few placed along the piece of metalwork. No cost.

Bullits graphs above are fixed angles for a year but when you optimise the tilt every month the benefits are higher as each month is maximised.

I tilt March, Mid May, Sept, Nov. I drilled the holes for every month optimal angle but don't bother tilting every month, if I did there would be further gains (but incremental at best).

Agree to disagree, if ground mount tilting costs a lot (it shouldn't) or you don't want the effort to do it, then not for you.

Likes of EML thinking off grid the Winter tilting is something to seriously consider

paulbok

Quick question, will a 800w micro inverter for dual panels, each with their own mppt tracker, be able to take one panel facing east and the other west?

ELM327

Am on deemed export so no intention of adding to the numbers I export.

The aim is to export zero.

unkel

https://www.boards.ie/discussion/comment/120249211#Comment_120249211

Yep

DC999

Very good article from Economist. Tldr is in the title and description ‘War and subsidies have turbocharged the green transition. They may have knocked as much as ten years off the timeline’. I was freaked out at start of the war that we’ve moved right back to dirty fuels (like coal) and had gone backwards on emissions. UK opening 1st coal mine in decades is an example.

I don’t have that fear now and haven't when I've seen the global 'double down' from governments to untie energy supply from certain monopolies. And this article shows how large parts of the world are now chucking money at renewables to reduce cost of energy. Some headline (+ hopeful) stats from it:

1.  “At €257 per megawatt-hour (mwh), the average price in Germany in December, a typical solar plant takes less than three years to become profitable, against 11 years at €50 per mwh, the average spot price between 2000 and 2022.” -afaik Germany has one of most expensive costs for energy in EU
2. Last year global capital expenditure on wind and solar assets grew from $357bn to $490bn, surpassing investment in new and existing oil and gas wells for the first time.
3. The iea expects China to build renewable-generation capacity capable of supplying 1,000 terawatt-hours by 2025, equivalent to the total power generation of Japan today.
4. All told, the iea expects global renewable-energy capacity to rise by 2,400gw between 2022 and 2027, an amount equivalent to China’s entire installed power capacity today.
5. America’s Inflation Reduction Act (ira) earmarks $369bn of subsidies for green tech; the European Commission plans to provide at least €250bn ($270bn) to clean-tech companies, and has decided to bring forward the target for doubling the eu’s installed solar capacity to 2025, from 2030. National ambitions have been supersized, too. In July Germany raised its target for the renewable share in power generation by 2030 to 80%, from 65%. China’s 14th five-year plan for energy, released in June, for the first time sets a goal for the share of renewables in power generation (of 33% by 2025). The country’s provincial governments are also increasingly offering green incentives.”

Talks about the cons too that a lot of this money won’t be efficiently spent. Same any time there is a huge spend on something. Supply and demand (huge demand will push prices up). Inflation will gobble up parts too. So it’s a balanced article I feel.  

Link: War and subsidies have turbocharged the green transition | The Economist

Need to register and can then read for free. Italics are snipped from article. Btw, can sign up to good weekly newsletters from them and get to read a few paragraphs to get a sense of the story. Then uses one of the free articles to read the full thing.

DC999

Heatpumps look to be getting much more affordable in UK according to this article. Under 2.5k post grant. That is same price as a gas boiler here.

I know devil is in the detail and likely a lot of small print and optional extras on top. But still a positive sign - for those with a house suited to a heatpump.

Says "Meanwhile, a heat pump price war is hotting up in the UK. Octopus Energy announced this week that it is launching a heat pump that will be as cheap as a gas boiler (£2,500 after factoring in the government’s Boiler Upgrade Scheme grant of £5,000).

The move was a reposes to British Gas’ recent pledge to offer the UK’s cheapest installation, starting from £2,999."

https://www.positive.news/society/good-news-stories-from-week-7-of-2023/

Need to scroll down a few stories to see it.

the_amazing_raisin

Going back to ground mounted PV, has anyone done or seen a sort of freestanding sun shade with solar panels? As in the lowest point would be around 2m from the ground so you can walk under it and not split your skull open

Be quite happy to do a DIY or kit job

bullit_dodger

ELM came across this last night while browsing youtube - though you might be interested.

(89) Uncover the Surprising Truth About Off-Grid Solar: Shocking Revelations You Need to Know! - YouTube

Personally I think he spent WAAAY over the top for that ($5000+/1Kwp), but the array's look impressive all the same. Not sure I'd like those in Ireland though. Pretty big sails. He talks about "ohh we get big winds up here - sometimes 40-50Km/hr" - not sure how they'd fair with a 100Km/hr gale coming in off the Atlantic! LOL. Would rather 1x single row of panels to reduce the leverage effect.

Also, lots of things I personally would question. For example he mentioned like electricity being "inefficient to heat water", but overall it's nice to see the scale he had. He also reckons (like I do) that Dec is a write off..as is Jan mostly for us in Ireland.....sun just isn't strong enough, although in his case it was more clouds than low slant angle/short time.

ELM327

Cheers, am going to watch that through now. I think I saw one of his videos befopre but I wasnt subscribed in any case. Nice ground mounts too.

Edit: Man, he overpaid for the storage. But I can I suppose understand not wanting to assemble 96kWh of calb cells lol

unkel

Found it hard to keep watching after I saw those 18 * 5kWh packs that he paid $27k for 🙄

the_amazing_raisin

https://www.boards.ie/discussion/comment/120267035#Comment_120267035

Capitalism at it's finest 😂

Ubbquittious

https://www.boards.ie/discussion/comment/120249211#Comment_120249211

Should be grand

jkforde

https://www.boards.ie/discussion/comment/120262008#Comment_120262008

thanks for that positive.news link, that's a great site! 👍

DC999

https://www.boards.ie/discussion/comment/120268951#Comment_120268951

Tbh if I could get a heatpump for the same price as a gas boiler and run the same rads, I'd bite their hand off. We've a leaky house so COP wouldn't be super but would still be decent. And it would force me to start to fill the small gaps that air leaks from.

unkel

https://www.boards.ie/discussion/comment/120269310#Comment_120269310

Air to water installed for €3k? That will never happen.

Like yourself, I'm keen to move to electric heating with a heat pump at some stage. But for that sort of money we will be looking at a few mini splits air to air.

At the moment I'm using 100% efficient COP 1 heating😂 and my gas boiler hasn't been on for days. Heating my house and my water right now from purely PV (not even from the battery)

DC999

Man, I’m a sucker for these good news stories about an energy efficient future😊 This is about district heating systems going live in Dublin.

Tldr: Amazon data center in Tallaght is now ‘dumping’ (in a good way) waste heat from the data center into a 1km pipe feeding into TU (Technological University Dublin), Tallaght. Win-win as Amazon dump the heat for free (saves them paying for cooling and using heaps of power to do that). And the Uni get heating at a lower cost as they only have to ‘boost’ the heat coming in to bring it up to temp.  

Technology is call district heating systems. Already well used afaik in other countries in high density places already where there is a heat source – also run from geothermal heat sources.

Ringsend Incinerator plant is also looking or already has a pilot to do the same to feed the buildings close to it along the Liffey at Point Depot end. It produces vast amounts of heat of course as it burns a huge % of Ireland's waste. Was at a talk from them before and they said the Ringsend Incinerator plant is hugely more efficient at producing heat than electricity. So better it goes into district heating.

At least some of those new dockland building are ‘district heating systems’ ready. Nor sure if it’s in the regs they need to be. I worked in one of them a few years ago and they were looking to start a pilot to try it. Any building with high density is a decent candidate to accept that heat. Those new 5-6 story office buildings on the Quays in Dublin take 600+ people.

Links:

• Link for TU story: Heat from an Amazon Data Center Is Warming Dublin's Buildings (reasonstobecheerful.world)
• 2021 Ringsend Incinerator article: Ringsend incinerator to supply heat for 30,000 more homes – The Irish Times. And a council source on that one says “We estimate 75 per cent of the buildings in Dublin would be suitable for district heating”
• And if you really wanna geek out, 2022 SEAI report on district heating (which I haven’t read): District Heating and Cooling | National Heat Study | SEAI. Read as far as line 1 😉 - that says “Ireland ranks in the bottom five in the EU for the shares of district heating and renewable heat.” But we’ve a huge number of data centres that are perfect to feed that. Give us the TLDR on that if you read it!!

paulbok

I alway wondered why more use of the 'waste' heat from data centers wasn't used before. Those too far from anything to have district heating, should have commercial greenhouses beside them, growing fruit/veg/and other heat loving plants 😜

The devils

https://www.boards.ie/discussion/comment/120271347#Comment_120271347

Yep saw the pipes first hand, they run from incinerator down under east link Bridge and under the liffey..I manage to walk it years ago..didn't go under the tunnel at the liffey :) To much vermon..it was suppose to heat lots of council house/complexes originally..hopefully it gets completed in the future.

DC999

https://www.boards.ie/discussion/comment/120272284#Comment_120272284

Yeah, I've been hearing about it for years but it hasn't taken of - like you say. For whatever reason. Maybe it was less a priority as everywhere had a heat source already. Price of gas and oil and electricity will have made it more a priority now I hope.

the_amazing_raisin

Installation completed today, 15x Jinko 420W panels and a 6kW Sofar hybrid inverter 🎉🎉🎉

Having great fun watching the MyEnergi app and seeing how much we're generating. Been steady around 1kW so far today so I'm very impressed considering it's February

No battery yet, but that's coming when SEAI pays us our grant

The Zappi should absorb any excess and send it to the car, so not an urgent problem to solve

Very happy so far 😁

Next step will be to ring the electricity company and tell them to f**k off, and then politely ask them to reduce my monthly payment 😂

the_amazing_raisin

Actually here's a question I have while I'm waiting for the battery

At what point is it better to import a little bit from the grid than export anything?

I've worked it out to be around 50% green energy for me, but I'm interested in hearing other views

Basically, I'm on deemed export, so the goal is to use as much as possible

At the moment, my day rate is around 30.26c and night rate is 14.52c

So if more than roughly 50% of my energy is coming from the panels, then it's cheaper than night rate

What I'm trying to figure out is, is it better to run appliances during the day, even if they're importing a bit of power, as long as I'm over 50% from the solar panels?

I'm going to have to run them anyway, and if it's cheaper than night rate it seems like the best option

Obviously the simplest solution is a battery, and then I don't have to overthink it, but before that happens I'd like to run as cheaply as possible

unkel

Don't overthink it, but the most efficient is to run them during the day "directly" from PV (well obviously via the inverter), unless that means you don't have enough battery to get you through the evening until night rate again

If your battery is big enough, you don't really have to worry about any of that anymore. Or what anyone does in the house with electricity use. And no more need for any micromanagement apart from periodically changing the amount of electricity you take in from night rate, from full battery from November / December to none at all from March or so until late summer. That's what I'm doing now, but I have 11kwp and 45kWh battery

the_amazing_raisin

https://www.boards.ie/discussion/comment/120275600#Comment_120275600

Well the plan is to get a battery soon, so I don't have to micromanage it. This is while I'm in the pre battery state and have to do everything manually

I'm probably checking the app every 5 seconds and I've only been generating PV for 3 hours 😂

unkel

https://www.boards.ie/discussion/comment/120275618#Comment_120275618

Ah sorry, misread your post, thought you had a (small) battery already. Still wouldn't overthink it and it depends on the sort of day and what size system you have. But if you're micromanaging, on a blue sky day like today, with a small to medium size system, just run 1 machine at a time from about 10:30 to 14:30. This ideal period obviously gets longer and longer towards the end of June

the_amazing_raisin

https://www.boards.ie/discussion/comment/120275641#Comment_120275641

Actually I think you're right not to overthink it.

Currently pulling 3.2kW from the panels, 0.2kW going to the house and 3kW going to the car. As long as I've got some clear skies, run something and worst case it'll be mostly free

Loving this so far, the missus is already asking how we can get the bill down to zero 😂