Private companies are allowed to invest in power plants in hydroelectric and non-conventional energy sources, provided that the Costa Rican Electricity Institute (Instituto Costarricense de Electricidad, ICE) purchases the electricity produced. 35% of the capital stock of the company must be owned by Costa Rican nationals. Participation of foreign capital in public or private legal persons entering into joint ventures with the Public Services Company of Heredia (ESPH) is limited to a maximum of 49% of the capital stock. There is no restriction on foreign investment in electricity generation for own consumption.
"ARTICLE 1.- Definition.
For the purposes of this Law, autonomous or parallel generation is defined as the energy produced by power plants of limited capacity, belonging to private companies or cooperatives that can be integrated into the national electricity system.
The electrical energy generated from the municipal solid waste processing will be exempt from the provisions of this Law and may be acquired by the Costa Rican Electricity Institute (ICE) or the National Power and Light Company (CNFL), according to the rates approved by the National Electricity Service (SNE).
ARTICLE 2.- They are power plants with limited capacity, hydroelectric power plants and those not conventional that do not exceed twenty thousand kilowatts (20,000 KW).
ARTICLE 3.- Public interest.
The purchase of electricity, by ICE, from cooperatives and private companies in which at least thirty-five percent (35%) of the capital stock belongs to Costa Ricans, who establish power plants with limited capacity to exploit the hydraulic potential on a small scale and from non-conventional energy sources, is declared of public interest.
ARTICLE 4.- Conventional sources of energy are all those that use hydrocarbons, mineral coal or water as a basic element.
ARTICLE 5.- Powers of the SNE.
The (SNE) (*) will have the power to grant concessions destined to exploit power plants of limited capacity, up to a maximum of twenty thousand kilowatts (20,000 kw) and for a term not exceeding twenty years.
Likewise, it may extend these concessions, modify or transfer them, without requiring legislative authorization; but this requirement will be essential when the exploitation exceeds twenty thousand kilowatts or the purchaser has approved concessions that, added to the new one, exceed that amount.
The kilowatt limit established in the previous paragraph will also apply to concessions that are granted in favor of individuals or legal entities that are not contemplated in articles 1 and 2 of this Law. From these provisions, the CNFL is exempted.
[...]
ARTICLE 20.- Authorization for the purchase of energy.
ICE is authorized to purchase electricity from privately owned power plants, up to fifteen percent (15%) in addition to the limit indicated in Article 7 of this Law.
This authorization is to acquire energy from hydraulic, geothermal, wind and any other unconventional source, in blocks of no more than fifty thousand kilowatts (50,000 kw ) of maximum power.[...]" (Law no. 7200 Authorizing Autonomous or Parallel Electricity Generation (09/28/1990), last amended by Law no. 8114 of 07/04/2001, Articles 1, 2, 3, 4, 5 and 20 [google translation]) 
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"ARTICLE 1.- The Public Services Company of Heredia is transformed into a public utility company with an indefinite term, called Public Services Company of Heredia Sociedad Anónima, whose name may be abbreviated Empresa de Servicios Públicos de Heredia SA, hereinafter, the Company.
The registered office of the Company will be the city of Heredia.
[...]
ARTICLE 15.- The Company is empowered to establish strategic alliances with persons of public or private law, provided that the latter have at least fifty-one percent (51%) of Costa Rican capital and their foreign participants have recognized technical and moral prestige. by the National University, with the purpose of financing, investing and developing the necessary projects to provide the services that have been entrusted to it. When the alliance with public law entities is established, no type of contest will be required; However, if it is carried out with private law persons, the Company will determine regulatory procedures that comply with the principles of publicity, equal opportunities, free competition and reasoned resolution.
Likewise, for the fulfillment of its purposes, the Company may acquire by any title; movable or immovable property, real or personal rights, you may also mortgage, lease, lease, pledge in any other way or possess and dispose of them. In addition, it may grant guarantees, provided that it obtains some economic benefit from this, it may confer powers when it suits the interests of the company and establish trusts.[...]" (Law no. 7789 on the Transformation of the Public Services Company of Heredia ESPH (04/30/1998), last amended by Law no. 8660 of 08/08/2008, Articles 1 and 15 [google translation])
Law no. 7200 Authorizing Autonomous or Parallel Electricity Generation (09/28/1990), last amended by Law no. 8114 of 07/04/2001, Articles 1, 2, 3, 4, 5 and 20 
Law no. 7789 on the Transformation of the Public Services Company of Heredia ESPH (04/30/1998), last amended by Law no. 8660 of 08/08/2008, Articles 1 and 15
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