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Alex Simmons

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Alex Simmons last won the day on March 16 2018

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About Alex Simmons

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    Transitions Legend!

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    Bellingen, NSW

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  • Year of first Tri race?

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  1. I paid for mine from savings (cashed in an investment or two). The ROI for my solar project (>20%) is much higher than pretty much any investment I have, so it wasn't a hard decision to make. The only reason I didn't so it sooner is I wanted to do roof restoration and tree felling/lopping work first.
  2. I think if you need to finance the system, this is a good low cost finance option. Especially as the QLD Govt interest free loan for solar scheme closed for applications a few weeks ago. But I would suggest increasing the home loan repayments by the amount you are saving on the electricity bills, at least until you have paid back that portion of the loan + interest. This should take 3-6 years depending on the individual variables in play. There after you are in front. The Qld scheme: https://www.qld.gov.au/community/cost-of-living-support/concessions/energy-concessions/solar-battery-rebate/about-the-program
  3. Solar PV output varies through the day, starting at zero when there is insufficient light, increasing through the morning to reach peak output during the middle of the day and then dropping back to zero as the daylight draws to an end. Add in clouds and rain at times and the output will vary based on the amount of sunlight reaching the panels. So yes, of course at any moment the panels can produce more, or less or the same as the amount of power your home is currently using. When the panels are producing in excess of what you are using, the inverter will divert that excess back to the grid. When the panels are producing less than you are currently using, the inverter will divert all of the available solar PV power to the house, and the balance needed to meet your demand will be energy from the grid. Obviously at night there is no solar PV production and all your energy comes from the grid. The inverter manages this process at the millisecond level to constantly ensure it maximises the use of solar PV. The system prioritises using your own solar PV power first, then it will either import the balance needed, or export excess generation. This is why doing what we call "load shifting" is a good thing - IOW choosing to run energy hungry devices during periods of high solar PV output. That way you reduce grid imports more as that has a better financial return than exporting the excess and running those devices during times when you'll need to import some or all of the power. Examples are clothes dryer, clothes washer, dishwasher, pool pump. Run them during the day and use the solar PV rather than in the evening. Most new systems installed today (on homes with sufficient roof capacity) are 6.6kW of panels with a 5kW inverter. There are various reasons for that, the main ones being: - most homes have single phase power and distribution companies limit export to a maximum of 5kW per phase - roof sizes and designs (multi directional roofs are common now) make this a practical limit for many common rooftops (commonly you can get there with 20-22 modern panels rated at 330W or 300W each). Panels are gradually increasing their output ratings over time, and we'll begin to see panels get closer to being rated at 400W in the years ahead. - the govt rebates you can get are based on panel peak capacity and you are permitted to have up to 133% of the inverter's rated output. Hence 6.6kW of panels with a 5kW inverter. As it turns out, it is a very good idea to "oversize" the panels as it makes far more efficient use of the inverter - they will actually work better that way (they lose efficiency at low power outputs). Keep in mind the panels are rated at their peak output, which they'll only ever do when the sun is high in the sky and the temperature is not too hot. At all other times they will produce less than their peak rated output. As a result, exceeding the inverter's rated output of 5kW only happens for brief periods of the day during the summer season, and so the loss of excess production is usually limited.
  4. I've had one for quite a few years now. Has the incident record button (which creates a separate file covering 30-sec before and after your press it) and the auto incident if it detects a big enough bump. Mine is recording at pretty hi res, at least double that of FHD and mean number plates are easily read. My card will store about 6-7 hours and over writes oldest recording as it goes. It has its own small screen, or you can plug it into laptop via USB or take the memory card out to view. That wifi connection roxii has sound good. It has an optional separate GPS device which I don't have, which will record typical GPS device data including speed, time, location and have that stamped onto the video. What prompted me was to have something for when I drive commissaires in bike races to provide some evidence for my own benefit in case of incident. I had the unfortunate experience of having a rider go down right in front of me just as they passed my car (when returning from the convoy) and disappear out of my sight. It would have been good to have had that on video to back up the witness statements made to Police. In case you were wondering, my reactions saved the rider who got away with a broken collar bone. I took the car right over a very deep culvert to avoid them. We were all very lucky that day. Back when I last drove at the Cadel Evans Great Ocean Road race a few years back, I used it there and the ranking UCI official (who was a great Commissaire, we were doing Comm 3 that day) asked me all about it and took notes as he thought it was a great idea. I note now that the Commissaire vehicles in Euro races are now seemingly fitted with them as standard.
  5. Export tariffs are a helpful in setting a bottom line. In QLD domestic solar PV production costs about 7c/kWh over a 10 year time frame. Hence even a lowish feed in tariff is paying for the system without you doing anything. Any time you replace grid import with your own production, well you're ahead. We live/work from home and consume 55% of our solar PV production. Keep in mind we have a larger than typical system at 11kW.
  6. As to your mate, possibly that's the case depending on the available import and export tariffs, and cost of installing a system. In north QLD the export tariff is modest, about 7-8c/kWh. Solar systems cost ~ $1k/kW, so say $7k for a 6.6kW system. In northern QLD that'll generate about 10kWh/year if it's north facing. In worst case scenario you export all production and have no self consumption (would would offset higher import tariffs) 10,000kWh x $0.08/kWh = $800/year in export income. That's the lower limit of financial benefit. For a system that costs ~$7,000, then the simple payback is 7000/800 = 8.75 years (an ROI of 11.4%). An ROI of 11% is not exactly horrible. Now if you are using just 20% of the solar PV output to replace grid imports, then then it's (2000kWh x $0.29/kWh) + (8000kWh x $0.08/kWh) = $1,220, which is a payback of 7000/1220 = 5.7 years (ROI of 17.5%). As you can see, it doesn't take much daytime self consumption to make the ROI pretty attractive.
  7. Without knowing the terms of the contract being proposed, it's hard to say. If you like, contact me offline and I'll do some numbers for you and your wife and put some realism into the assessment.
  8. I pulled the trigger a couple of weeks ago to change to a TOU plan. It'll be ~$300/year better for us than the flat rate tariff. That's because 50% of our usage is off-peak and it brings the weighted average price down quite a bit.
  9. Yep, and they are not going to get you the best quality, the most suitable or the best value system. They are going to push the one that makes them the most money.
  10. When you instal solar PV system, you'll be required to change your electricity plan. In terms of what the financial benefits are, then the energy you offset with solar, plus the excess you export are both making you money and repaying the cost of the solar. In general replacing grid imports is worth more than exporting excess generation, but the export income is still very good value. Choosing the right plan to start with isn't so easy, so as a rule of thumb, go for a plan with the smallest difference between the import tariff and the export tariff. Then as your actual energy use patterns emerge, you can assess whether moving to an alternative plan is more suitable.
  11. Personally I would steer well clear of any installer that does door to door, or has advertised promotions like on TV. These are the categories with the highest chance of getting hit by a dodgy brother's outfit. It's not a highly regulated industry and there's plenty of crap solar installers out there. It's imperative you deal with a quality installer. This isn't a bad start on questions: https://www.solarquotes.com.au/fb-13-questions.html and if you want to be contacted by quality installers in your area, try https://www.solarquotes.com.au/ or https://www.solarchoice.net.au/
  12. Alex Simmons


    Yes. All I can say is look for a professional to assist you with the process. It is quite intimidating and a bureaucratic black hole.
  13. Probably (e.g. the GP 5000), but I don't do Crr research. There are a few places that do, e.g.: https://www.bicyclerollingresistance.com/ but this is by no means the only source. Yes and they will always provide a lower Crr than a butyl equivalent. If speed matters, then use a good latex tube. Higher pressures are only desirable on near perfect surfaces, e.g. an excellent wooden velodrome. In just about every outdoor environment we experience in Australia I would expect 90psi will more likely yield a lower Crr than 120psi. Most people over inflate their tyres.
  14. At steep gradients this accounts for around 90% of the energy demand. At shallower gradients though the less linear this relationship becomes and energy demand is more shared amongst factors other than an increase in gravitational potential (e.g. overcoming air and rolling resistance). Another fun fact: Coefficient of rolling resistance is effectively equivalent to gradient. e.g. a Crr of 0.005 (0.005=0.5%)* is the same in energy terms as adding to the 0.5% gradient. IOW choosing low rolling resistance tyres (or using the right tyre pressure) is akin to choosing to ride up a less steep hill. * About the Crr of good tyres on a typical asphalt road
  15. What brand of random number generator are you using to *cough* measure that?
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