- What is a kilowatt hour?
The difference between kilowatts is the rate of power at any instant and kilowatt-hours is the amount of energy being used. A light bulb does not use 50 watts in one hour, it uses 50 watt-hours in one hour. The "hours" part is important and without it we'd have no idea what period of time we were talking about
The rate of electrical use at any moment is measured in watts. For example:
- A 75-watt light bulb uses 75 watts.
- A typical desktop computer uses 65 watts.
- A central air conditioner uses about 3000 watts.
If your appliance lists amps instead of watts, then multiply the amps times the voltage to get the watts. For example: 2.5 amps x 120 volts = 300 watts
- The rate of electrical use at any moment is measured in watts. For example:
To know how much energy you're using you have to consider how long you run your appliances. When you run a 1 watt appliance for an hour, that's a watt-hour. It's abbreviation is; Wh.
- One 75-watt light bulb on for an hour is 75 watt-hours (75 Wh)
- One 75-watt light bulb on for six hours is 450 Wh
- Five 75-watt light bulbs on for an hour is 375 Wh
1,000 watt-hours is a kilowatt-hour (kWh).
- One 100-watt light bulb on for an hour is 0.1 kWh (100/1000)
- One 100-watt light bulb on for ten hours is 1 kWh (1 bulb x 100W x 10h= 1000Wh = 1 kWh)
- Ten 100-watt light bulbs on for an hour, is 1 kWh (10 bulbs x 100W x 1h= 1000Wh = 1 kWh)
- Ten 50-watt light bulbs on for an hour, is 0.5 kWh
- Ten 100-watt light bulbs on for 1/2 an hour, is 0.5 kWh
- Running a 3000-watt air conditioner for an hour is 3.0 kWh
- How tall should the mounting pole be?
The mounting pole can be as low as 10 feet, for building top mounting all the way to 40 feet in hiegth for residential, commercial or industrial installations. This depends on your location and any obstructions there might be around the area you wish to install your turbine. As with any small wind turbine, the higher up the turbine sits above any obstructions the better your power production will be. The only caveat is the cost of the mounting pole. The taller the pole the more expensive it will be including the amount of concrete and rebar that will be needed in the foundation.
- What are rotor startup and shutdown speeds?
The Venger Wind turbine will start spinning at about 2.25m/s - 8kph - 5mph. It is self-starting and requires no power to spin up. It does not need over speed control because of it's design and will continue to output power in wind speeds over 144kph unless you own a V2 turbo which was designed for lower wind speed regimes.
- How much power will the Venger Wind turbines generate?
- The V1 2kw system with an average wind speed of 5m/s – 18kph - 11mph will average between 742 kWh per year with a k factor of 1.5
- The V2 4.5kw system with an average wind speed of 5m/s – 18kph - 11mph will average 1,684 kWh per year with a k factor of 1.5
- The V2 Turbo 4.5kw system with an average wind speed of 5m/s – 18kph - 11mph will average 3,084 kWh per year with a k factor of 1.5
- What is K Factor?
Wind energy has been modeled statistically by engineers in an effort to quantify power potential in different geographic areas. The Wiebull statistical distribution has been found to most closely resemble the variability of wind patterns. An important determinant of the Wiebull distribution is the K factor. A K factor approaching 1 indicates highly variable wind while a K factor near 3 signifies constant or regular wind which is ideal for energy production.
- What is Wiebull Statistical Distribution?
Wind is not steady and in order to calculate the mean power delivered by a wind turbine from its power curve, it is necessary to know the probability density distribution of the wind speed. For those unfamiliar with statistics, this is simply the distribution of the proportion of time spent by the wind within narrow bands of wind speed.
For a more detailed scientific explanation: http://en.wikipedia.org/wiki/Weibull_distribution
- How close can these turbines be mounted to each other?
The distance between turbines depends on the individual install site. Some locations with strong prevailing winds can have adjacent turbines 0.5 meters apart if they are installed in a counter rotating configuration. A traditional configuration would have them 1.8 – 3.6 meters apart to minimize shadowing which can reduce electricity production. The optimal layout places consecutive counter rotating turbines in a line perpendicular to the prevailing wind.
- How well does the Venger Wind turbine stand up to harsh environments?
All materials and finishes were selected and designed to exceed military level specifications for survivability in extreme environments. Should you have special requirements for additional survivability standards, Venger Wind can customize systems for your application. Please keep in mind that use of these turbines in a highly corrosive environment such as the planet Mercury might not be possible and cost prohibitive, however, if a real need arrises we can give it a try.
- What safety features do the turbines have?
The Venger Wind turbine is constructed of high strength aircraft aluminum and is designed for extreme environments. The modular blade structure provides redundant load paths making a durable platform. The unit has a built in generator brake for shutdown and maintenance purposes. Under normal expected conditions there is no need to stop the turbine, it will operate safely in winds of (160kph, 100mph) unless you own a V2 Turbo which was designed for lower wind speed regimes.
- Many manufacturers say no brake needed, but then define a survival wind speed at 40-55m/s?
Full Question: Which is normally ok, but what’s happening if the wind speed is higher in a hurricane? We’ve already seen many turbines breaking much earlier than defined survival wind speeds. That’s why I think a break is needed, also for maintenance. You are not allowed to do maintenance on a cell tower if the turbine is rotating?
Answer: We have two different safety systems that brake the system so it does not exceed a predetermined RPM level. The first is through the inverter where it senses the RPM and if it starts to exceed a preset value the power is diverted to the diversion load as needed so the system does not exceed that RPM. The second solution is with our Venger Smart Box which effectively does the same thing but can also stop the turbine from spinning. Our turbine disconnect box shorts the generator windings which locks it in place for maintenance.
- Does your system have accreditation?
We supply the Aurora One Grid-Tie Inverter which has CE and UL listing which will allow you to connect to the grid.
- What exactly is performance definition: wind-power, rotor-power, generator-power or grid-power?
Full Question: Your performance values are looking a bit smaller compared to other vertical wind turbines with similar size. Furthermore, it’s not clear what exactly they mean with their performance definition: wind-power, rotor-power, generator-power or grid-power?
Answer: We have found that many competitors do not properly state their power outputs. We've taken a lot of time to make sure our system meets what is stated. Although our system may be physically larger than our competitors for the same amount of power we do offer a much faster payback period as our system is priced lower than our competitors for the same amount of power production. Our power is grid power.
- How does Venger define the monopole requirements against statics, torsion and wind load?
Full Question: How does Venger define the monopole requirements against statics, torsion and wind load? I see that that you recommend 1 - 6m, which is then far too small for a cell tower. Or can we mount it on top of a cell tower (40 - 55m height). Is it recommended to go as high as possible as wind speed is then much better?
Answer: Yes, higher is better. We just happen to offer solutions between 1 and 6 meters currently but can offer higher heights if needed. Our tower mounting option will allow you to be about 20M above the ground with a direct mount to the side of the tower. The system can be mounted much higher on the tower depending on the strength of the tower design.