13

A specific answer to your very narrow question wouldn't be much use to anyone else; and you haven't given us enough information to give you a specific answer anyway. But what we can do, is give you the types of information you'd need to make a decision. And I'll restrict it just to PV and wind, as that's what you've asked about; others reading this might ...


12

Disclosure: Doing things such as this is my 'day job'. You can use a bicycle dynamo to recharge a suitable battery at very little expense and with minimal effort. Use of something like the "Reecharger" that you mention is not essential, does extremely little for you and, if their description of their own products are accurate, the Reecharger is a badly ...


10

There is an empirical measure. Install a small weather station device and record the wind conditions. Then you can compare your charts to what turbine vendors promise and see how much of the time you have enough wind for the turbine to be useful.


9

DC motors: The most suitable motors are those which have permanent magnets in their rotors. Traditionally these were pure DC motors - where DC was fed into the motor rather than AC such as is obtained from AC mains or via a transformer, but the boundary has become blurred as a BLDC motor or BLDCM = "Brushless DC Motor" uses electronics to take supplied DC ...


9

In Ireland, electricity is equally likely to be from renewable sources during the day as during the night ENTSO-E, the European Network of Transmission System Operators for Electricity, provides a transparency platform where you can see the hourly actual generation per production type for Ireland: It's hard to pick out a trend just by looking at a day ...


7

TL;DR: Wind is not dead, but a diverse set of economic, technical, and political factors have resulted in a leveling off of the rate of new construction. The cost to build new wind declined for years but has leveled off From the U.S. Energy Information Agency: Early wind project developers snagged the best sites As costs declined, developers ...


6

According to the REN21 Renewables Global Status Report 2014, China had 91.4 GW of installed wind capacity by the end of 2013, more than any other country in the world, of which 75.5 GW was in commercial operation. The USA had 61.6 GW of installed wind capacity. In terms of actual generation from wind, the USA was world leader in 2013, with 19.4 GW mean ...


6

Wind turbines do not turn the ground between them into desert. There is still farming and growth of various plants (even trees) possible. It should not be excluded in those comparisons and calculations. A wind turbine with 3MW power, rotor diameter of 100 meters rotating at a hub hight of 100 meters may allow growing plants with a height up to 25 meters (~ ...


6

There are two parts to the answer. One is enlarging the geographic area of capture of wind and solar across diverse climates, to smooth out the exogenous variations. The other is is storage. Span more climates Back in the early noughties, Gregor Czisch built a massive optimisation model to look at how to balance a 100% renewables grid at lowest cost, ...


6

One approach is to look for studies in this area and decide whether the idea is even plausible. Is it "a bit more expensive but I like the technology" or is it "much more expensive and doesn't work very well"? If it's the former you can start looking at your exact site, if the latter... do you have a lot of money to spend on something that just looks green? ...


6

Summary We typically get about 20-30 times as much energy out as energy in. The range in the literature is wide: 4.6-40. Overview The ratio of energy generated to energy invested will vary, depending on a lot of issues. Here, I'll only consider grid-scale wind power, i.e. turbines of 0.5MW rated capacity upwards. That's because they represent the ...


5

In what sense of sustainable? I assume you mean profitable, since you use "economical" as a synonym in the text. A short, brutal answer is that a small unit in an urban area is unlikely to generate enough electricity to even cover maintenance costs, so it's not ever going to be profitable. The problem is that smaller turbines are more expensive ($/watt), ...


5

There are three broad approaches to dealing with variable generation: Diversity of supply: Both through building a grid covering a wide area (see EnergyNumbers' answer for details) and by using different sources of generation. As an example of the latter, consider a grid powered by both wind and solar sources: these are likely to provide peak output at ...


5

If you have a single-string MPPT charge controller, then you should not even think of trying to combine your two generators (i.e. PV array and wind turbine) onto a single input and feeding that in. The voltage produced by most simple (i.e. cheap/beginner/entry-level/DIY) wind turbines varies with wind speed. If you combine this in series with your PV array ...


5

Executive summary It's too early to tell what the resale value is, as contemporary turbine designs are not as old as the lifetime of a wind-turbine, so we have very little experience of the economic value that results from decommissioning 1.5MW turbines; however, a rough first-order calculation puts the scrap value of the metals, based on Feb 2016 UK prices,...


5

I'll give you an answer based on my previous readings and some years of researches/talks and practices about this subject. But I think that you can only reduce costs if you know and take into consideration: Your living situation: land owner, family situation (kids, pets, ...), etc. Your objectives: eat organic food, reduce carbon emissions, religious ...


5

A tree farm of that size in a temperate climate would only produce ~1.7GWh/y (net). You are overestimating the productive value of trees by a factor of ~15. A 5MW wind turbine can produce a maximum of ~44GWh a year. Your assumed figure of 1GWh is only 2.3% of its rated capacity. No-one would bother financing/building a turbine on that site if they could ...


5

It doesn't. Assuming you're referring to wind capacity additions, it most closely tracks the political winds in the U.S., in the form of the Production Tax Credit (PTC), a federal incentive program for construction of new wind capacity. The U.S. Department of Energy's Wind Vision report makes this relationship clear: This chart ends at 2013 when the ...


5

The second slide of the presentation linked by you actually shows the issue with wake very clearly. You could also talk about turbulences instead of wake (my company actually does). Wake is simply the pertubation of the flow of the wind by wind turbines (or any other object, like hills, trees, buildings, airplane noses, the grill on the new SUV by Chrysler, ...


5

Since raw materials scale according to size, every different panel/turbine will have a different answer. Different generators also have different maintenance costs, and lifespans. It's probably more meaningful to look at the total — lifecycle — cost of generation, not just a generator's initial construction cost. Carbon Brief have a 2017 article that ...


4

Firstly, if it's rooftop wind you're asking about, then that's easy: it's not worth it - the air's too turbulent. But if it's a pole-mounted turbine that you're considering, then talk to a supplier or installer - they'll have the right kit for you to hire cheaply. It's best to measure speeds at the hub height you have in mind. It's just an anemometer and a ...


3

I'm not an expert on the topic but I have been doing similar research for the past several months as I'm planning to build an off-grid home and, obviously, renewable energy is critical for me. As LShaver has suggested, wind turbines are probably not the best option for an urban environment. You (probably) won't have strong and constant wind to generate ...


3

With any given engineering field there is a learning curve. With wind turbines there is a big incentive to go big. The higher up you are, the more wind. In addition in many cases, it's easier to get permission to redevelop an existing wind farm with larger turbines than to get permission to build a new one. Also higher air is less gusty, and taller ...


3

I have some knowledge in this field, coming from several years' experience in drafting and defending patent applications that deal with wind turbines in one form or other. If you're talking about a single wind turbine with a sensor somewhere on the nacelle, downwind of the rotor blades: one way of dealing with the problem of wake-corrupted measurements is ...


3

From the Wind Measurement International site: P90 is all about quantifying the uncertainty of annual energy yield predictions. P90 is the energy WMI predicts that a wind turbine is 90% likely to produce over an average year, given the uncertainties in the measurement, analysis and wind turbine operation. P50, on the other hand, is the average annual ...


3

In most situations, they are a toy. One thing comes up over and over on various other sites: Height is critical. The minimum height you should consider is 30 meters. 50 meters is better. This is likely to get you noticed by your neighbors. Ideally you want to be 30 meters above the surrounding wind deflecting obstacles such as other houses and trees. ...


3

Added at start: To answer this question at the depth requested could require a few reams of paper and its own website :-). The original statement about repowering was somebody's simplificatioin of one small part of a complex ongoing process. The basis for the claim can be seen in various sources but it is arguably not justified as a pithy one line ...


3

Combining wind turbine and solar panel is my favorite (that has not come to reality by now...). Both of them are weather dependent but in an almost anti-correlated way. It means they complement each other very well most of the time of the year. Here in continental Europe, usually when it's a sunny day it's rarely windy. And when the weather is changing or in ...


3

https://www.renewables.ninja/ will give you a crude estimate. But it's not very useful - it will often be very wrong for onshore wind. In general, for any onshore wind, or any offshore wind close to shore, we're some time away from being able to do this usefully. The input data that's required just isn't available. It's a much more difficult problem for ...


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