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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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  • Location
    Bellingen, NSW

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  • Year of first Tri race?
    1900

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  1. I was already mates with TUV via cycling, but I will never ever forget his support helping me get through one of the worst days of my life some 12 odd years ago. It's hard to express how important it was having a mate on my side in those long long minutes (hour) between crashing and being carted away in the meat truck. He was also a witness during my court case. Not seen him for some time and was good to hear he's enjoying life.
  2. Provided the consumption is during solar production hours. The same could be said about having higher power tariffs too. Which is why it's mostly about lowering your total energy expense than it is about chasing the best ROI figure. The latter can be artificially manipulated to some degree while not actually achieving the most important outcome, i.e. saving money (or reduced emissions if that's more important to you, although these objective align nicely). Aside from solar PV, I also did some things in the year or two before solar PV went on to help with energy consumption, like replacing the old pool pump with a highly efficient model that saved ~ $500/year alone in reduced power bills. I have other things I want to do to reduce consumption, improving the thermal characteristics of this old house being the main one. It means the ROI for our solar PV drops, but our actual expenditure on energy does as well. The latter is more important.
  3. Update, I just got my latest quarterly bill giving me a full year of bills since installing solar PV. A reduction of $3.1k in annual bills. On track for a payback period of 4 years. It'll be about the only chance for an apples with apples comparison of before and after bills as from early next year a new granny flat we are building will be occupied changing the energy consumption. Quarterly Bill Comparison Before and After Solar PV Quarter Before* After^ Difference Jan – Apr $1,561 $587 -$974 Apr – Jul $886 $379 -$507 Jul – Oct $1,001 $82 -$919 Oct – Jan $1,297 $566 -$731 ------------------------------------------ TOTAL $4,745 $1,614 -$3,131 * Average of the quarterly bills for the two years prior to installation of solar PV system ^ 11kW PV, 10kW inverter, Rural Mid-North NSW
  4. Alex Simmons

    Calculating FTP

    Just on the FTP thing, if the number is higher from outdoor riding, that will be your FTP. That you can't sustain as high a power output indoors doesn't mean your FTP is lower, rather the conditions are such that you are unable to fully express your aerobic capability. Same with impacts of altitude, heat etc. What to do about it? i. do the things I mention in my blog item to see if the gap between power output inside and out can be narrowed, and/or ii. training should always be relative to what you can do. Using a proportion of FTP to set a training level really is just a starting guide. If you know that you are 20W lower on a trainer, well you should expect to adjust power levels for trainer work accordingly. Pithy Power Proverb: "Alls you can do is alls you can do."
  5. Alex Simmons

    Calculating FTP

    It's worth checking. What sort of power meter? Pacing well takes a bit of practice, so just chalk it up as a learning experience and a nice bit of training. One trick with such tests is not to think of them as taking precisely 20-min, rather start out conservatively with power/effort, and then gradually increase it as you feel you can. It will take several (3-5) minutes of riding before you can begin to really make that judgement as perception of effort take a while to catch up with reality. So say after 5-min then again at 10 and 15 minutes, gauge how you are feeling and whether you can pick it up a bit more, or not as the case may be. If you find that as you approach 20-min you are riding a significantly higher power than you did in the first 5-min, then just go longer, add 3, 4, or 5 minutes to the end of the effort at the higher power and simply use the best 20-min power as your result. Threshold will be roughly that best 20-min less about 7% give or take a few%. You can narrow it down a bit more by adding a mean maximal effort of ~4-6 minutes on another day. Those two efforts can be combined with a simple model to come up with a better estimate of FTP than say using "95% of 20-min test". Forget about cadence and just ride they way you feel you can get the power down for the effort. No, it's not relevant to the questions you ask. It's only relevant in the context of those seeking to validate quoted power numbers. Power numbers quoted at the higher end tend to elicit more suspicion from a jaded online public, because unfortunately experience in the online world suggests there are a fair share of those quoting vanity/fantasy/unrealistic power numbers. Often however it's just because the person is not experienced with such things and they don't know if a number is valid or not for them. It might just indicate a problem with the measurement process or the device, and of course it's also entirely feasible these numbers represent reality. As I said in another response above, there are many factors in play that can see indoor and outdoor power differ, aside from validating any differences in the actual power measurements themselves. I wrote this piece 10 years ago to go through some of those factors: https://wattmatters.blog/home/2009/01/turbocharged-training.html Hope that helps.
  6. Alex Simmons

    Calculating FTP

    There are many factors in play when considering the power one can sustain on a trainer compared with out on the road. In some cases it will be similar, some people can actually sustain more on a trainer while most experience their outdoor power to be higher than on a trainer by handful of percent. It can also be quite a large difference. I know for instance on a crappy old magnetic resistance trainer I once had I was at least 15% down on my outdoor power. It was horrible to use. When I upgraded to a custom made trainer with a massive flywheel and double reduction gearing, the gap between my indoor and outdoor power narrowed quite a bit and the last 20W (at threshold) I was able to close by getting a power industrial fan for cooling. Both trainers and power meters can be accurate or inaccurate. It depends on the trainer and the power meter and the user. A quality power meter used correctly will be accurate in the face of variable conditions experienced outdoors. A quality power meter can also be woefully inaccurate on a trainer if not used correctly. The primary factor influencing muscle fibre type recruitment is power output. A modestly lower or higher cadence at similar power output isn't going to make much difference to fibre type recruitment.
  7. Alex Simmons

    Calculating FTP

    1. What sort of power meter? 2. Is it calibrated and are you checking torque zero? 3. What are you using to inspect the data? 4. There can be a difference between power you can sustain on an indoor trainer and outdoor riding. What sort of trainer? Do you have sufficiently effective cooling?
  8. This is a comparison of our quarterly bills before and after solar PV. Pre-solar is an average of the quarterly bills for two previous years. Quarter Pre-solar Post-solar Difference Apr – Jul $ 886 $ 379 -$ 507 Jul – Oct $1,001 $ 73 * -$ 928 * Oct – Jan $1,297 $ 566 -$ 731 Jan – Apr $1,561 $ 587 -$ 974 ---------------------------------------------- TOTAL $4,745 $1,605 -$3,140 * estimate with one week remaining in billing period
  9. That's a really nice gain considering the time of year.
  10. Better than peak hot water! Guess it depends on what tariff your HW is using as well of course as to how much HW you use. Ours is on a controlled load (different to off-peak) and costs a tick over $200/year. We use ~5.0 - 5.5kWh/day on average for HW. Old fridges can be pretty energy hungry. Newer tech is more efficient and also doesn't have the same level of high power draw when they start a cooling cycle. Hot water is an interesting conundrum. The best solution for reducing costs depends on several factors and will vary by individual household. For us there is no gain to be had from installing either a solar thermal HW system or a heat pump HW system (heat pumps use about 1/4 of the energy of a standard electric HW tank). That's because these systems cost a LOT more up front compared with a standard electric resistance HW tank and since we can only reduce our HW expense by at most $200/year it's just not a big enough annual return to justify spending several thousands of dollars more on a solar thermal or heat pump system. For homes with high HW expense, then these options become more viable. Another option is using excess solar PV to power a standard resistive element HW tank (can also do this with heat pump unit). This method makes sense if your off-peak tariff is somewhat higher than your feed-in tariff. HW can't be on a controlled load for this solution to work though. In some locations there is no controlled load available and so people are on TOU tariffs and HW is on a timer for off-peak tariff heating. As a rule of thumb, off-peak tariffs are generally somewhat higher than controlled load tariffs. The cheap and cheerful way is to put the HW circuit on a timer and have it come on when the solar PV is most likely to be generating significantly more than general household demand. This works most of the time but on occasions your solar PV won't be able to supply enough power (cloudy/rainy day) so it will also draw some energy from the grid at daytime import tariffs. It's a function of seeing how much excess daytime energy you produce on average during various times of year, how that compares with total HW energy demand and what balance will come from grid imports. IOW the average tariff paid for HW will be something 85% FIT + 15% daytime tariff. Then seeing if that weighted average tariff is much better than current off-peak tariff. Another option is to use smart control electronics that monitor solar PV output and household consumption and turn on the HW circuit only when sufficient excess PV power is available. Unfortunately these control devices are not cheap. Fronius have their Ohmpilot, but it's ~$800 plus install, so again the ability to recover that investment means you need to have large tariff differences and HW consumption for it to be worthwhile. In my case my FIT > controlled load tariff, so there just isn't a way for me to do better. Diverting solar PV to heat hot water instead of exporting would increase my electricity bills. For those with gas HW, well gas prices suck.
  11. I've no issue with companies making money! It's an option worth considering and these sort of roof lease deals are something more common in some parts of the USA. I just think they could do better with the tariffs they are offering. Provided the risks are well considered and mitigated, it's a way to save money now. The downside is not being able to save more later. Weighing that up takes a bit of cash flow analysis and some assumptions. As the market matures further, then solar PV sales will become like cars and will really be about selling finance. The physical product or service is sort of secondary to the sale of money.
  12. I think those tariffs are pretty ordinary. The daytime tariff is double their cost of supplying power via the solar PV and the evening power tariff is just them getting full rack retail plus some extra margin on top by looks of it. I just don't see the incentive given the risks involved.
  13. Are these the tariffs just for electricity imported from the grid, or for all of your energy consumption? What is the process to review/change these tariffs over time?
  14. That sucks. Pension isn't income?! What kind of stupid shite is that? (I don't expect an answer).
  15. Ah, small business. Hurry up and wait! Good luck with it. Was wondering how you got on.
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