SolarQuotes Blog

I'm not sure where you are, and what regions the vendor I'm using covers, but I did pick Beyond Solar. This was mostly because my neighbour, an ex-power plant engineer, with much more expertise in this tech than me, had selected them three years ago, and his son had gone through a similar process a month or so ago and also chose them. Quality of the equipment is the big factor, and I gather a lot of the significantly cheaper companies are cutting costs on the quality and/or warranty. I was recommended https://www.solarquotes.com.au/ by several trusted sources for comparing options, though didn't end up using them.

An interesting little "gotcha" to this (unless I'm mistaken, please correct if so) is that imported energy is not taken into account. The UK recently ran 2 weeks "without using coal" [1], but this completely ignored any imported energy which did [2]. So, this is great - provided we don't simply pass the buck (like by sending all of our plastics to Asia). Edit: Provide citations [1] https://www.bbc.com/news/business-48473259 [2] https://www.solarquotes.com.au/blog/britain-coal-record-mb1079/ (11.8% imported)

Yes, it's actually pretty common. See comparisons across generating technologies in "An international comparative assessment of construction cost overruns for electricity infrastructure" [1]. Here's what the researchers found for solar (section 3.4): Thirty-nine solar PV and CSP power plants, representing 2374 MW of installed capacity and $16.5 billion worth of investment, were analyzed. (These are utility-scale infrastructure projects, thus they do not include the familiar rooftop solar collectors on buildings or residential configurations.) These projects as a class actually came in $4.2 million less than budgeted, or $200,000 less than expected per project. These solar systems had the lowest average cost escalation per reference class (1.3 percent), the least time overruns (an average of 2 months ahead of schedule), and the lowest standard deviation for amount of overruns and time overruns. They also had the largest total amount of cost underruns, with the entire class of projects costing $163.9 million less than budgeted, though some of this may be explained by dramatic reductions in cost over the past 4 years. As Table 5 indicates, only 3 facilities had overruns greater than $50 million and only 3 facilities had cost overruns greater than 30%, all of which were CSP facilities rather than large-scale solar PV apparatuses. Here are a few solar projects that outperformed in recent years: O'Brien solar farm in Wisconsin, completed in 2021, on time and under…

It's mostly just costs. See Figure 1.2 Global weighted average LCOEs from newly commissioned, utility-scale renewable power generation technologies, 2010-2021 https://irena.org/-/media/Files/IRENA/Agency/Publication/2022/Jul/IREN… Hydro costs are going up, solar and wind going down. Hydro is still less than fossil fuels, which is great, but that's not the target to beat anymore, and renewables are lower and trending even lower. And that's before the more extreme geographical constraints for siting, with good locations already used, the project sizes and the longer lead times and investment paybacks compared with renewables. But Hydro also has flexibility, which is really useful for balancing renewables and nuclear. It's important to switch existing Hydro into this mode to make the most of it. But again, for new build, since the raw power is more expensive than renewables, the flexibility would need to be cheaper than the equivalent flexibility provided by more renewables plus batteries to win back that lost ground. And it isn't. Same story for pumped storage. Here's a worked example for the Snowy 2 project: https://www.solarquotes.com.au/blog/snowy-2-vs-battery-storage/ The key thing is, energy production is cheap these days. So storing energy has to compete against just building even more production and a small amount of storage. This applies to batteries as much as it does to hydro. But batteries scale down better.

You pay a higher daily supply charge and more per kWh outside this window so it's more like free (conditions apply) The supply charge is 6% higher for the Solar Sharer plan, while the peak rate is 92% higher. Solar Sharer’s peak rate is almost double the flat rate. The off-peak rate is 17% lower than the flat rate. https://www.solarquotes.com.au/blog/solar-sharer-plans-compared/

This is sort of over stated generally. In Australia where North is “optimal”, even South facing panels produce only 20-30% less and East/West about 15%. It does vary a bit by latitude but it’s not at all pointless to install them in other orientations in many places. I have not done the math to see how much of the world this extends to, but it applies to a fairly large chunk of Australia. Source: https://www.solarquotes.com.au/panels/direction/ Tesla’s system also had non solar tiles so you could just skip the panels in whichever parts you wanted. Roof construction is quite different here to the US though. We never have the plywood layer, it’s either ceramic tile or Colorbond steel directly onto usually wooden sometimes steel beams.

This makes perfect economic sense, without any environmental arguments. Rooftop solar now produces 11.2% of the electricity in the Australian market [1], as it's the cheapest source of electricity. That percentage is not a peak value, but averaged across the year. On some summer days, rooftop solar is effectively powering the entire grid and is having to be throttled. That 11.2% only includes the power that enters the market. It does not include power which houses generate and consume on-site, which does not pass through the meter, so the actual percentage is higher. [1] https://www.solarquotes.com.au/blog/australia-solar-2024-mb3086/

The new Tesla Powerwall 3 is $13,600 https://www.solarquotes.com.au/blog/powerwall-3-launch/ Two of those is $27,200 minus installation and some solar panels to feed them (but the PW3 does have 3x 6.6kW solar MPPTs built-in unlike previous ones, so all you need to do is connect the panels directly to the PW3 and then the PW3 to your home).

Another interesting example is Southern Australia. It also went from coal to renewables, and also with gas as "backup". Its just fascinating how far they have come, from less than 1% renewables in 2007 to more than 60%, all without any hydro which makes reneables "easy". https://www.solarquotes.com.au/blog/sa-renewables-milestone/

Sun Cable's 10GW in the Northern Australia is also ground mounted: https://www.solarquotes.com.au/blog/sun-cable-5b-solar-mb1185/

Snowy 2's actual storage capacity is estimated to be ~40 GWh https://www.solarquotes.com.au/blog/snowy-2-vs-battery-storage/

I think Australia will use mostly batteries, but we are building more hydro. I think hydro is miscast as being green though, when in reality it causes enormous ecological destruction. Hydro is also intermittent - it requires the right amount of rainfall, currently hydro in Australia is not able to reach full generation because it will flood downstream as it's been a wet year. Hydro is not that cheap (depending on the metric you need) - see an example[1] comparing Australian hydro to the aforementioned Victorian Big Battery. [1] https://www.solarquotes.com.au/blog/snowy-2-vs-battery-storage/

It absolutely can be, in Australia we have several players involved and from what I understand, integration is dictated by the network operator. Eg, provided the battery used supports VPP, you can join under a number of different providers offering different contracts. See here [1] for a comparison table. [1] https://www.solarquotes.com.au/battery-storage/vpp-comparison/

You can easily throw solar panels in a land fill. It isn't a big problem. Slag heaps from coal is already a much larger problem than a solar panel landfill would ever be. A single coal mine has a bigger slag problem than all the worlds solar panels combined. Yes, we should take the problem serious, but it is also grossly overrated. It is certainly not a reason to avoid solar panels. https://www.solarquotes.com.au/blog/recycling-solar-panel-waste/

PowerWall scales fine, like most things do, with infinite money. All you need is a ~$10K [1] investment (including installation) for every house every 10 years (warranty period) and voila - grid scale! Oh warranty doesn't cover normal degradation of energy capacity over time. [2] [1] https://www.energysage.com/solar/solar-energy-storage/tesla-powerwall-… [2] https://www.solarquotes.com.au/blog/new-powerwall-warranty/

TIL, never seen a DC-coupled PW2 in the field. Looks like it was killed off in 2017. (i.e. before PW2 was widely available) https://www.greentechmedia.com/articles/read/the-new-tesla-powerwall-i… https://www.solarquotes.com.au/blog/tesla-kills-off-dc-powerwall-2-ac-…

You mean the Redflow ones? They do look interesting, I haven't heard much about them for a while but here's a review from 2016: https://www.solarquotes.com.au/blog/redflows-zinc-bromide-zcell-batter… Ah, it sounds like they went quiet while setting up manufacturing facilities in Thailand and have recently started marketing again: https://redflow.com/redflow-on-growth-trajectory-after-emerging-from-a…

Rooftop solar is on average a $25,000 - $35,000 investment, and that's not even counting energy storage required to actually be off-grid. I don't think that only the rich should have reliable energy, and the poor should suffer brownouts to theoretically save some infrastructure costs. I'm assuming you are talking USD, if so? Are you sure you have your numbers correct? That seems ridiculously expensive compared to say Australia. First link on DuckDuckGo: https://www.solarquotes.com.au/panels/cost/

Gas is faster to respond, coal, not so much. From the Goog: Starting up a coal-fired power station depends heavily on the plant's current temperature, taking anywhere from 2 to 48 hours to reach full operational capacity. Because of massive metal boilers and turbines, the heating process must be slow to prevent severe thermal fatigue and equipment damage. [1, 2] The startup time is broken down by the plant's previous state: • Hot Start (less than 8 hours offline): 2 to 4 hours. The boiler and equipment are still warm, allowing for a relatively quick resumption of steam production. • Warm Start (8 to 120 hours offline): 4 to 8 hours. • Cold Start (More than 120 hours offline): 12 to 48 hours. The plant must be heated from room temperature, which involves initially burning expensive natural gas or diesel just to safely warm the furnace and metal pipes before coal can be introduced. [1, 3, 5] To explore how these heavy thermal operations impact the broader electricity supply, you can review the U.S. Energy Information Administration's grid reliability data or dive deeper into the technical challenges via the Environmental Protection Agency's Coal Startup Report. [6] If you are interested in the broader power market, let me know: [1] https://www.quora.com/Why-its-not-that-easy-to-start-operating-power-p… [2]…

> What's the term of the load in your calculation? What do you mean by that? The amount you can draw from the power walls? This page has a chart with specs that cover this: https://www.solarquotes.com.au/blog/tesla-powerwall-2/ I think each powerwall can draw 5 kW continuous and 7 kW peak. > A PowerWall has a 10 year lifespan, where they guarantee that batteries will have 70% capacity or better during that time. I take this to mean you'll need to size for a 30% capacity drop, and plan for battery replacement in 10 years. Well, it has a 10 year warranty, not life span. Yes, for sure there will be some degradation with time (although for my car, a Model S, I'm surprised that after close to 5 years and 25K miles I barely "lost" 1% of range). It depends on how you draw and charge. > Does your loan factor in installation costs, which can be significant? I believe it does, and also includes the rebates/credits. But you can answer those questions yourself by going to their website and doing a "pretend order" - that'll give you a bunch of knobs to play with and see the various options between buy cash vs loan. > Since the goal is to reduce the chance of fire, what would the probability of starting a fire be with thousands of powerwalls installed all over the place be in comparison? Well, the goal isn't just to reduce the chance of fire: it's also to offer availability at reasonable cost. Some will also like the "independence" aspect of it, like "stick it to the man" - but…