Auroracoin is a decentralised, peer-to-peer, and secure cryptocurrency released as an alternative to the Icelandic Króna to bypass governmental restrictions associated with the national fiat currency. It was launched with the aim of becoming the ‘official’ cryptocurrency of Iceland. AUR was a pioneer in the area of country-specific cryptocurrencies. AUR was launched on the 25th of January, 2014, by an anonymous developer who went by the pseudonym of Baldur Friggjar Óðinsson. It was originally based on Litecoin, using the Scrypt algorithm with a Proof of Work mechanism, but was later updated to use a multi-algorithm architecture in 2016, forked from DigiByte. Auroracoin uses the PoW consensus mechanism, which utilises device hashing power to solve a complex mathematical problem in order to authenticate a transaction proposed to be stored in the blockchain. The difficulty of solving the problem ensures that authenticating forged transactions is very difficult unless the attacker owns an impractically large chunk of the network’s total hashing power. AUR is one of the only cryptocurrencies to use a combination of five different hashing algorithms, namely Grøstl, Qubit, scrypt, SHA-256, and Skein. While initially very popular, Auroracoin has seen little to no activity for a while, with poor marketing, and frequent dev team changes. Reasons for little growth have been various, from slow adoption in Iceland, to developers leaving and joining the project midway. However, it is expected to not go lower than the recent low, and might see a rise as AUR plans to launch a more aggressive marketing campaign in Iceland to promote the coin among the masses. Unlike most other altcoins, Auroracoin has made extensive changes to the original codebase. It has introduced security measures such as Automatic checkpointing, and protecting against known flaws present in the BTC blockchain, such as 51% block replacement attacks.
Solarcoin is a Scrypt based alternative digital currency and its innovation comes from the secondary proof of work reward: the Solar Proof of Work. Green solar energy producers are entitled to receive one SLR for every MWh electricity generated. In order to claim a Solar Proof of Work reward, solar plant owners must submit 3rd party verified energy generation certificates such as a Solar Renewable Energy Certificate (SREC) or equivalent country specific documentation. All Solar Proof Of Work rewards will be stored as transactions in the blockchain. The supply of SLR comprises of the following: - The Mining Pool: 105 million Solarcoins (0.1%) to be publicly mined over the next 40 years. All publicly mined Solarcoins represent historically generated and unclaimed solar electricity. - The Generator Pool: 97.5 billion SolarCoins (99.4%) are currently stored in the OCA non-circulating generation pool account. These will be exchanged for Solar Proof of Work claims of solar electricity generation submitted over the next 40 years at the rate of 1 SLR per MWh of solar energy. - The Genesis Pool: 500 million Solarcoins (0.5%) are stored in the genesis pool account for environmental charities, early volunteers, advisers, builders and maintainers of SolarCoin infrastructure. Genesis pool circulation is capped so that it will never represent more than 5% of total Solarcoin in circulation.