How much solar energy available?

by | Aug 27, 2018 | Articles, General, SRW, SS

 

How much solar energy available?

How much solar energy available depends on locality, cloud cover and season. This article explains how it’s measured and how to know exactly.

How much solar energy hits the earth

Yearly global solar input. Solar power is totally feasible in most areas between 50 degrees latitude (north to south).

Currently, 7000 times more solar is available than we need for power worldwide. It is 800-1000 watts for every flat square metre. Right now our solar modules 14% to 20.5% efficient. This provides 120 to 140 watts per square metre.

Solar reality is less than some expect

We can visualise solar as much as like rain, but rather measuring in a rain-gauge, we can visualise light as ‘filling’ a standard-size ‘light bucket.’  The industry calls each ‘bucket full’ as one Peak Sun Hour (1 PSH). Later in the day, the bucket may take two hours to fill (i.e. 0.5 PSH) – and so on . . .

In areas like central Australian or Arizona etc there’s 5-6 PSH/day much of the year. During a Melbourne or Madrid mid-winter, however, it will be far less. There, solar input may be as low as 1-1.5 PSH. It may also have major local variations. Googling PSH (or ‘solar input’) for your locality usually produce an answer. If not, your Meteorology Dept will advise.

You can also obtain exact data about knowing how much solar available. Establish your geographic coordinates (via Google or a good map), then open https://eosweb.larc.nasa.gov/cgi-bin/sse/grid.cgi?email=skip@larc.nasa.gov. Enter your data where shown. Open the table ‘Radiation on an Equator-pointed Tilted Surface’. (By ‘Equator’ NASA means solar modules facing south in the northern hemisphere, north in the southern.) The data is an ongoing ten-year average. It shows optimal solar module tilt angles. Five to ten degrees difference causes only minor change. The table also shows how to gain more input in winter (at the expense of summer). And vice versa. Some people make them adjustable but solar capacity is so cheap it costs little to add more if you space to locate them.

See also: https://rvbooks.com.au/battery-capacity-required-for-home-and-property-solar/

Solar energy available – how and where to go from here?

Knowing how much solar energy available indicates whether it is worth going ahead. How to proceed from here is covered in my two globally-selling solar books. Both are down-to-earth English and technically correct. My bio is at: https://rvbooks.com.au/collyn-rivers/

For all you need to know to install solar for homes and properties – buy Solar Success. That for boats, cabins and RVs is in Solar That Really Works! and Caravan & Motorhome Electrics. See also Our all solar house.

If you are interested also in RVs – see our associated rvbooks.com.au

Collyn Rivers is a semi-retired automobile research engineer.  He is the author of seven books, five of which are about making RVs and solar work optimally.

Caravan and Motorhome Electrics

The essential handbook for anyone with an RV of any kind.  Everything you need to know to make the electrics in your rig work for you.

Cover of Caravan and Motorhome Books by Collyn Rivers

eBook versions

Paperback version

The book retailers set their own prices which can vary substantially. We'll aim to keep a selection of the better prices above.

Any bookshop, whether online or bricks and mortar, can order copies of Caravan & Motorhome Electrics.  Just ask.
ISBN: 978-0-6483190-8-5

Solar Success

Whether you’re building a new home or adding solar to an existing structure, this is the one book you can’t afford to be without.

eBook versions

Paperback version

Any bookshop, whether online or bricks and mortar, can order copies of Solar Success.  Just ask.
ISBN: 978-0-6487945-4-7

Why Caravans Roll Over
and how to prevent it

Explains in detail every aspect of tow vehicle and caravan stability. This is what you need to know to be safe on or off the road.

eBook versions

Paperback version

The book retailers set their own prices which can vary substantially. We'll aim to keep a selection of the better prices above.

Any bookshop, whether online or bricks and mortar, can order copies of Why Caravans Roll Over.  Just ask.
ISBN: 978-0-6483190-6-1

Solar That Really Works!

Solar that Really Works! covers the design, installation and use of solar in cabins, camper trailers, caravans, fifth wheelers, campervans and motor homes.

eBook versions

Paperback version

The book retailers set their own prices which can vary substantially. We'll aim to keep a selection of the better prices above.

Any bookshop, whether online or bricks and mortar, can order copies of Solar That Really Works!  Just ask.
ISBN: 978-0-6483190-3-0

The Caravan & Motorhome Book

The Caravan & Motorhome Book covers every conceivable aspect of campervan and motorhome usage. If you own a camper van or motor home, you'll want this book.

eBook versions

Paperback version

The book retailers set their own prices which can vary substantially. We'll aim to keep a selection of the better prices above.

Any bookshop, whether online or bricks and mortar, can order copies of The Caravan & Motorhome Book. Just ask.
ISBN: 978-0-6483190-5-4.

Caravan and Motorhome Electrics

The essential handbook for anyone with an RV of any kind.  Everything you need to know to make the electrics in your rig work for you.

Cover of Caravan and Motorhome Books by Collyn Rivers

eBook versions

Paperback version

The book retailers set their own prices which can vary substantially. We'll aim to keep a selection of the better prices above.

Any bookshop, whether online or bricks and mortar, can order copies of Caravan & Motorhome Electrics.  Just ask.
ISBN: 978-0-6483190-8-5

Solar Success

Whether you’re building a new home or adding solar to an existing structure, this is the one book you can’t afford to be without.

eBook versions

Paperback version

Any bookshop, whether online or bricks and mortar, can order copies of Solar Success.  Just ask.
ISBN: 978-0-6487945-4-7

The Caravan & Motorhome Book

The Caravan & Motorhome Book covers every conceivable aspect of campervan and motorhome usage. If you own a camper van or motor home, you'll want this book.

eBook versions

Paperback version

The book retailers set their own prices which can vary substantially. We'll aim to keep a selection of the better prices above.

Any bookshop, whether online or bricks and mortar, can order copies of The Caravan & Motorhome Book. Just ask.
ISBN: 978-0-6483190-5-4.

Solar That Really Works!

Solar that Really Works! covers the design, installation and use of solar in cabins, camper trailers, caravans, fifth wheelers, campervans and motor homes.

eBook versions

Paperback version

The book retailers set their own prices which can vary substantially. We'll aim to keep a selection of the better prices above.

Any bookshop, whether online or bricks and mortar, can order copies of Solar That Really Works!  Just ask.
ISBN: 978-0-6483190-3-0

Why Caravans Roll Over
and how to prevent it

Explains in detail every aspect of tow vehicle and caravan stability. This is what you need to know to be safe on or off the road.

eBook versions

Paperback version

The book retailers set their own prices which can vary substantially. We'll aim to keep a selection of the better prices above.

Any bookshop, whether online or bricks and mortar, can order copies of Why Caravans Roll Over.  Just ask.
ISBN: 978-0-6483190-6-1