Remember that the business model of these companies is the same as cable companies. They are depending on monthly fees from you for the rest of your life for their ET signal. To determine the annual penalty that your clients will suffer with ET broadcast services, multiply the number of controllers times the monthly fee times 12. Compare that high, recurring cost with the "no-fee" alternative offered by SunFall™ and Smart Timers™ from Accurate WeatherSet.
The purchases cost of those controllers is high because expensive radio receivers are required to communicate with orbiting satellites. The endless monthly fees will exceed the high initial cost of the purchase.
You still need to install a rain sensor for each controller because ET does NOT include local rainfall. If you install a rain sensor, you may as well install our SunFall™ sensor (shown to the right) with a Smart Timer™ and be free from endless monthly signal fees for broadcast ET. Also, you may need to mount their antenna remotely if the controller's view of the sky is blocked by steel and concrete. If it blocks the sun, it may block satellite signals.
Is it really ET that they are selling?
Broadcast ET companies emphasize the coverage of their broadcast. They spend much less time on discussion of the source of their data. For ET EveryWhere™ which is used by Toro and IrriTrol, HydroPoint states the following.
"HydroPoint collects, analyzes and validates weather data gathered from more than 12,000 weather stations across the United States. It utilizes these existing weather stations to provide input parameters for its local ET calculations. The primary weather station data comes from the National Oceanic and Atmospheric Administration (NOAA) weather network, which is also used by key organizations such as the National Weather Service and US Military, for mission critical applications."
The NOAA weather network is NOT designed to guide watering of lawns, and we understand that "mission critical applications" of the US Military do NOT include watering grass. The NOAA network is designed for public safety, not water conservation. It informs the public of
- rain, snow and icy conditions,
- frost warnings,
- high and low temperatures,
- wind shear and other high winds, and
- hurricanes and tornadoes.
The NOAA's weather stations measure
- temperature and humidty,
- wind speed and direction, and
- barometric pressure.
NOAA's most impressive and well funded tool is Doppler radar which is completely useless in ET.
The state and local water agencies recognized the inadequacy of NOAA as a tool for water conservation. In the 1970s, they researched electronic weather stations. In the 1980s, they designed special weather stations (shown to the right) for the needs of water conservation under pressure from agriculture to grow healthier crops and to reduce pumping costs. They are called CIMIS stations in California, AZMET stations in Arizona and other names in other states. As a group, these specialize weather stations are called ET weather stations or ET Stations. These water agencies mandated the inclusion of solar sensors in their ET weather stations because solar radiation is the driving force in photosynthesis, plant cooling (transpiration) and evaporation from dirt. NOAA has no interest in these landscape processes.
These state water agencies have different equations to process their weather data. But, all these equations give a dominating influence to solar measurement. When you go to these state web sites and study their daily data, you will often see marks next to individual data entries indicating that some daily measurement is "out of range." If the datum is NOT solar, then the ET networks give an ET number for that day. But, solar data are so important that if they are "out of range," then no ET numbers are given for those days.
We are certain the ET broadcast services use data from
high-quality ET weather stations where available. But remember that these ET stations where designed and installed for agriculture. So there are very few ET stations in cities, and finding 20 acres for future ET stations will be a big problem in cities. In the hot interior valley of Los Angeles (San Fernando Valley), there is no ET CIMIS station, and 1.2 million people are watering their lawns.
We applaud the pioneering work of HydroPoint in explaining to numerous audiences the value of ET and the importance of reducing runoff. We sympathize with the difficulties of extending ET broadcast services into cities using data that are below the standards of ET networks and remote from the sprinkler timers. We are participants in an effort by the water agencies to extend ET networks into cities in the "Non-ideal site program" of CIMIS and are making proposals in that effort with our SunFall sensor at the heart of our proposals. We believe that ET broadcast services and products are certainly better than conventional "dumb" timers that do not have input from the environment.
But, we have a better alternative that is low enough in cost to make SunFall™ measurements on every home and business.
SunFall™ is a great alternative to
ET EveryWhere™
and other broadcast ET services?
The California Department of Water Resources says that on average, 85% of their ET computation is based on solar and 10% is based on wind. When the air is calm, solar radiation is 90-95% of their ET computation.
Our Smart Timers™ take readings of solar intensity (watts per square meter) from our SunFall™ sensor all day long. At 8 PM every night, our Smart Timers™ convert these accumulated measurements into a number which we call SunFall™. As part to this conversion to SunFall, we add 8% to include the mid range of the other contributors to ET.
We believe that there are five reasons that SunFall™ and Smart Timers™ are a smarter choice than the Smart Dial from Irritrol, Intelli-sense from Toro and other ET broadcast services and products:
- more relevant ET data than NOAA;
- more accurate ET data than NOAA;
- on-site, real-time data rather than data from remote and scattered NOAA weather stations and broadcast to timers;
- absence of endless signal fees; and
- low enough in cost to put on every home and business.
We believe that SunFall™ and Smart Timers™ are closer to providing ET everywhere than HydroPoint's ET EveryWhere™ and their licensed partners of Toro and Irritrol. We know that Smart Timers™ with SunFall™ sensors will be much lower in cost to you to purchase and we will NEVER demand endless monthly signal fees from you or your clients.
from Toro, IrriTrol and HydroPoint
. . . . .
NO signal fees with SunFall™ and Smart Timers™
from Accurate WeatherSet
No endless, monthly signal fees,
with SunFall™ and rainfall sensors.
Let's start with the questions.
- Why pay for ET Everywhere™ when you only need ET on your site?
- Is it really ET that they are selling?
- Is SunFall™ a good alternative to ET EveryWhere™?
when you only need it on your site?
For ET computations, air temperature over 20 acres of well-maintained grass is important.
These differences in concerns led the water districts to develop stringent site requirements for ET weather stations that are very different from NOAA's site requirements. Click ET siting to see stringent requirements for ET stations.