• Wind Power
  • Solar Power
  • Radiation DB
  • PV Prediction

Wind power generation-related business

The JWA provides one-stop support for coordination with stakeholders, wind condition surveys, power generation estimations, optimal allocation of wind turbines, environmental consideration, environmental impact assessments, power generation predictions and bird strikes.

Coordination with stakeholders The JWA provides consulting on coordinating with fishery stakeholders, which is an important issue when planning off-shore wind power systems. We also support the promotion of understanding among local residents through environmental assessment procedures.

Wind condition surveys, power generation estimations, optimal allocation of wind turbines The JWA provides one-stop support for optimal site selection for wind observation poles and LiDAR installation, as well as installation, observation, data monitoring and storage and data analysis (power generation estimation based on simulations and optimal allocation of wind turbines).

Environmental Impact Assessments The JWA supports procedures for assessment under ordinance and voluntary assessments, including explanations at explanatory meetings for residents.

Wind direction and velocity predictions, wind power generation predictions Power generation amounts from the present time to 48 hours ahead are predicted.

Countermeasure against bird strikes JWA developed an automatic bird strike detecting system in cooperation with two private companies. It enables an automated remote detection of bird strikes at wind firm, even if it is an offshore station.

Increase in prediction accuracy by 20% due to statistical corrections

Wind, which is a motive power for wind power generation, is easily affected by the surrounding terrain. There are cases where accurate predictions are not possible simply by using prediction values from the meteorological model. Thus, based on statistical corrections using past measured values, systematic errors between the predicted values by the meteorological model and actual observed values at target sites were eliminated. By doing so, prediction accuracy increased by approximately 20%.

Increase in prediction accuracy by 50% due to sequential correction

Example of temporal change in prediction error based on sequential correction

By using the actual observed values for wind velocity and power generation output observed at target geographical points, it is possible to further correct predicted values (sequential correction). The effects of sequential correction are particularly large up to a few hours ahead, and prediction accuracy increases up to 50%.


Top share in Japan for environmental assessments related to wind power generation facilities

Consulting on methodology for shortening time spent on commercialization to the maximum extent, while maintaining the highest level for quality of environmental assessments

Experts are allocated for each survey item, ensuring quality for all surveys and analysis technologies

Bird strikes by migratory birds or birds of prey are surveyed using the latest technology such as radar and automated image monitoring system.

Solar power generation-related business

Using various data related to solar radiation, which serves as energy for solar power generation, and survey and prediction technology, the JWA supports the customers'introduction of solar power generation. Our one-stop support encompasses valuable services, from comprehension of potential quantity before introduction, estimation and prediction of power generation necessary for systematic operation after introduction, to fault diagnosis of solar power generation systems.

Solar power generation potential survey

The JWA conducts surveys by making use of solar radiation databases such as MONSOLA and observed data on spectral solar radiation, and using area-wide solar radiation estimation technology based on meteorological satellite images.

Solar radiation map

The solar radiation data in MONSOLA-11 is depicted (mapped out) on a map. It is possible to comprehend a geographical distribution of the solar radiation amount by month as well as annual average.


This is a database of cumulative daily solar radiation by month for 837 points throughout Japan. It is possible to display the solar radiation on inclined surface by tilt angle (in intervals of 10 degrees) and by azimuth angle (in intervals of 15 degrees) (Statistical period: 1981 to 2009).

Solar radiation prediction and solar power generation output prediction

Highly precise solar radiation estimation and prediction that is helpful for efficient operation are possible.


Consulting backed by decades-long survey and research performance related to solar power generation and solar radiation

Solar radiation and solar power generation for the period from the present to one week ahead can be estimated.

Intended purposes

Solar radiation database Comprehension of the potential quantity of solar power generation is used in feasibility assessments related to power facility sites

Solar radiation estimations/predictions Area-wide estimations and predictions of solar radiation and solar power generation amounts are linked to streamlining and higher precision of power supply and demand operation. Prediction of solar radiation and solar power generation amounts at specific points, such as mega solar power plants, is used in planning and adjusting operation for large-scale power facilities

Global database for estimated solar radiation values (SOLASAT-Global)

Estimation of global solar radiation

SOLASAT-Global is an offline service that provides "past data on estimated solar radiation values at arbitrary points around the world", using analysis technology for meteorological satellite images. Solar radiation values around the world are estimated in 5km grid intervals every hour from meteorological satellite images taken from a variety of locations, and these values are then compiled into a database. High estimation accuracy has been confirmed for SOLASAT-Global.

Accuracy validation sites

Time-sequence diagram for solar radiation (Rocksprings)


Meteorological satellite images from various satellites around the world are used

Solar radiation amounts from arbitrary points ranging from 80 degrees north latitude to 80 degrees south latitude are provided in a time series

Also supports calculation of statistical values (daily total values, yearly average values, etc.)

Intended purposes

Selection of optimal sites for constructing solar power plants around the world

Solar radiation data analysis for various sites around the world

Analysis of interannual valiabilities in solar radiation and solar power generation amounts

The solar power generation business is risky in that power generation amounts that were anticipated in the planning stage may not be achieved due to the weather each year.
With this service, the JWA provides the results of analysis of "the extent to which power generation amounts are changing depending on the year," and not only the average power generation amounts anticipated every year.

Support for profitability assessment of the solar power generation business through solar radiation and solar power generation analysis!

Analysis of actual observed or estimated solar radiation/power generation amounts over as long of a period of time as possible at arbitrary sites

Provision of various statistical information (average values, maximum/minimum values, standard deviation, occurrence rate, probability of exceedance)

Analysis of arbitrary tilt angle/azimuth angle that matches panel installation conditions

High reliability of analysis results, due to use of same estimation method as "NEDO solar radiation database (MONSOLA-11)," which is widely used as standard data for estimation of solar radiation amounts in Japan

Changes in solar radiation amounts and power generation amounts for each month and year over a long period of time can be comprehended visually and quantitatively. By comparing power generation amounts based on multiple hypotheses of tilt angles and azimuth angles for panels, it is possible to determine the optimal installation angle.

Information necessary for analyses

Position information for target sitesUsed in calculating solar radiation on horizontal surface

Panel tilt angle/azimuth angleUsed in calculating solar radiation on an inclined surface from the solar radiation on horizontal surface

Rated output/type/installation conditions of panelUsed in calculating power generation amount from solar radiation