If you don’t see your question or answer below, post it in the SolarCoin forum.

  • What is SolarCoin?
    SolarCoin is an alternative digital currency. SolarCoin is backed by two forms of proof of work. One is the traditional cryptographic proof of work associated with digital currency.  Another proof of work is a 3rd party verified meter reading. SolarCoin is equitably distributed using both of these proofs of work as a means to reward solar energy generation.


    Solar energy, unlike fossil fuels, does not place excess heat or carbon into the atmosphere. The long term intent is to provide an incentive to produce more solar electricity globally over the next 40 years by rewarding the generators of solar electricity.  SolarCoin is intended to shift the levelized cost of energy (LOCE). Source:solarcoin wiki

    Technical details relating to SolarCoin are on Github.com/solarcoin

    See what the World’s media is saying about SolarCoin.

  • How do I get SolarCoins?

    1. Download and install a wallet.

    2. Visit an online Charitable faucet run by 3rd party digital currency, Solar energy and environmental groups. A list of 3rd party faucets is maintained on the SolarCoin wiki page. Solar energy related charities may reach out to the SolarCoin Foundation for a SolarCoin grant for the charity and its members.

    3. Submit a proof of Solar electricity generation in the form of a 3rd party verified meter reading format based on your countries geography and or regulatory regime. 1MWh entitles you to §1 SLR coin.  On the Claim SolarCoins section of the SolarCoin.org site.

    4. Buy SolarCoin online on an exchange .

    SLR Grant

    4. Mine them like other alternative currencies: To mine them you need to download a SolarCoin wallet or join a mining pool.

  • How can I start accepting SolarCoins for my business or charity?

    1. Download a SolarCoin wallet from below.
    2. Find your SolarCoin address in the wallet application.
    3. Display your SolarCoin address or QR code on your website or on a physical sign.

    SolarCoin accepted here3
    That’s it! You can now receive SolarCoin as donations or payment for goods and services.

  • What is one MWh's worth of electricity?

    Each circulating SolarCoin represents 1MWh (megawatt hour) of solar electricity generated. Each MWh of renewable electricity displaces more than 1,500 lbs of carbon dioxide that would have been released by burning fossil fuels like natural gas and coal.

  • Who created SolarCoin and who is managing it?

    SolarCoin was created by a group of volunteers interested in creating a currency experiment to benefit the environment. SolarCoin is an open community project run by Volunteers working together as the SolarCoin Foundation.  Anyone can join and participate. See the volunteer page.  The SolarCoin Foundation is getting its charter together.  More early information is on the SolarCoin Wiki and SolarCoin SolarCoin forum

  • What is the SolarCoin Foundation?
    The SolarCoin Foundation is an international network of volunteers managing the distribution of SolarCoins to Solar Electricity Generators using 3rd party verified meter readings as the “proof of work”.

    The SolarCoin Foundation maintains a public ledger detailing each SolarCoin allocated to solar electricity generators. The transactions are also kept in the SolarCoin Blockchain.

  • When did SolarCoin start? How long is it going to last?

    SolarCoin was launched in January 2014.  The SolarCoin Foundation designed the supply of SolarCoin to last 40 years delivering incentives for generating 97,500 TWh of solar electricity. The SolarCoin network evolves as the adoption of the currency grows.

  • How are SolarCoins allocated?

    SolarCoins representing 97,500 TeraWatt hours of solar energy generation are held in reserve:

    • §105 Million SolarCoins (0.1%) will be mined. >98% of the §105 million minable SolarCoins will circulate in the next 6 years.  Mining generates 52.6 million SolarCoins in the first year halving each year after that. All publicly mined SolarCoins represent historically generated and unclaimed solar electricity. Technical specs are on github/solarcoin.  The Blockchain explorer is here.
    • §97.5 Billion SolarCoins (99.4%) are stored in the SolarCoin Foundation non-circulating generator pool account. These are to be exchanged for “proof of work” claims of solar electricity generation submitted over the next 40 years. Each 1MWh of solar energy is entitled to 1 SLR. According to the IEA were an estimated 147 Million MWh of Solar electricity produced by PV & CSP in 2013. This would equal 147 million potential SolarCoins claims.

    SolarCoin Issuance Process:

    -         Solar energy generated from a 3rd party verified meter reading

    -         SolarCoin Foundation & community verifies claim and records issuance in public ledger

    -         SolarCoin Foundation transfers coins from reserve account to claimant (visible in the blockchain)

    -         SLR claimant spends / circulates coins using wallets etc.

    • §500 Million SolarCoins (0.509%) in the genesis pool account representing environmental charities, early volunteers, advisers, builders and maintainers of SolarCoin infrastructure will circulate.  Genesis pool circulation is restricted to never being more than 5% of total SolarCoin in circulation.
    SolarCoins have been granted to 14 out of 215 countries so far. Claim SolarCoins here.
  • How can SolarCoin currency be environmentally friendly?
    SolarCoin is intended as a mechanism to incentivize generation of global solar electricity. Solar power is an abundant, renewable energy source that avoids pollution from conventional coal and nuclear plants. Every megawatt-hour of electricity generated through a solar PV panel avoids more than 1,500 lbs of carbon dioxide (CO2), more than 5 lbs of sulfur dioxide (SO2), and almost 2 lbs of nitrogen oxide (NOx), and it also avoids producing radioactive nuclear wastes.  Solar energy production is highest on hot, sunny days when air conditioners are running and electricity demand peaks.  By providing energy during peak demand times, that same solar energy that warms an area can be captured and used to power those devices.

    bitcoin solarcoin carbon footprint

    Using a marginal utility model based on Blockchain rewards, SolarCoin is estimated to be >50 times more energy and Carbon efficient than Bitcoin. Lower Carbon Currency Model explanation in wiki. Feel free to critique, enhance and propose a better carbon model Google Doc spreadsheet is here. Excel Spreadsheet model download.

    This estimate doesn’t include the effects SolarCoin may have on Solar energy generation. When the incentive for solar electricity generation is figured in, SolarCoin is likely to be extremely good for Carbon Reduction.  The SolarCoin Foundation welcomes those wishing to present models or papers supporting or refuting this early thesis.

  • How is SolarCoin different from Bitcoin?

    SolarCoin is not a replacement for Bitcoin. It is a complementary currency using Bitcoin technology implemented to incentivize global Solar electricity generation over the next 40 years.



    Incentivize global solar electricity for the next 40 years.


    Create a decentralized currency

    SolarCoin Foundation


    Satoshi Nakamoto


    Launch date


    Open source community

    Project support

    Open source community

    §98.10 billion

    Maximum issuance

    21 million

    <§16 million

    Current circulation

    >11 million

    Est. §60 million (§50 million mining §10 million charitable grants)

    Next years circulation increase

    Est. 1 million

    Free market supply & demand

    Currency target value

    Free market supply & demand

    Coins & paper wallets (bills) coming soon.

    Physical format

    Coins & paper wallets (bills)

    (Proof of Solar 1MWh generation, energy grants) & proof of cryptographic work by SolarCoin Foundation & algorithm

    Equitable circulation methodology

    Proof of cryptographic work by algorithm

    1 MWh of solar electricity generation

    Value representation


    Windows, Linux & MacOS & Android(soon)

    Operating Systems

    Windows, Linux, MacOS, Android & others





    Largest holder of circulating currency


    SolarCoin Foundation

    Largest holder of reserve currency


    $20 (4 year stable target)

    Market value


    1440 blocks (daily)

    Difficulty adjustment

    2016 (2 weeks)

    §100 SLR

    Initial block reward

    50 BTC


    Hashing Algorithm


    50% every 1 year

    Block reward decay rate

    50% every 4 years

    4 years

    95% public mining done

    17 years

    2040 (estimate based on Solar Energy production)

    95% in circulation by


    LiteCoin source code fork

    Source Code

    Bitcoin original source

    This Wiki Page highlights the primary differences. A Blockchain explorer is here.

  • Are there physical SolarCoins?

    There aren’t any physical SolarCoins in circulation yet. It is possible for people to create them in a fashion similar to physical bitcoins and paper wallets. A physical SolarCoin might look similar to this. The SolarCoin Foundation doesn’t endorse, verify or authenticate any SolarCoin issuer, producer, agency or service related to SolarCoin. A list of non-endorsed service providers including a SolarCoin paper wallet creator is available in the wiki page SolarCoin exchanges and other services.

    NewMockGold_1280x960SolarCoin Stack Small_1280x960

    SolarCoin Pile Large_1280x960

    These images are provided like all content on the site as creative commons with rights of attribution only. Available in high resolution upon request.